7. Description of the Mapping Units of the Arizona General Soil Map


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7.1. Basis and Development of the Units


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Arizona has a great diversity of soils that generally are distributed in an intricate pattern throughout the state. These patterns are produced by the relatively extreme differences of climate, vegetation, lithology and physiography that are compressed within the state's boundaries. One objective of the Arizona General Soil Map (Plate 1) was to organize this intricate geographic soil distribution pattern so that it is comprehensible. The map then is the basis for organizing and extending knowledge about soils pertinent to use or potential use and to scientific study.

Mapping units used in the Arizona General Soil Map (Plate 1) are soil associations. A soil association consists of a set of geographic bodies that are segments of the soil mantle covering the land surface (Simonson, 1971). Each association consists of polypedons of two or more soils that occur together in a characteristic and repetitious manner (Figure 40). Every delineated body of one soil association has the same major component kinds of soils occurring together in a similar pattern so that the patterns and proportions of major soils are alike within limits among the delineated bodies identified as a single soil association.

County soil maps were used in part to establish soil associations and prepare the map. General soils maps were available for each of the 15 counties but were prepared by different persons over a period of time. Few, if any, attempts were made to correlate soil associations in one county with those in another county at their common boundary. Consequently the mapping units of the counties were not uniform. Levels of generalization varied from county to county due partly to the availability or nonavailability of completed or ongoing standard soil surveys. Variability also was due in part to surveys conducted in response to requests about using soils for different specific purposes. The county general soils maps, then, were adjusted along county boundaries so that similar mapping units in bordering counties could be given similar names. It was necessary also to combine, rename and adjust units to stay within the number of units recommended for general soil maps (Simonson, 1971).

Little was known about the soils in some fairly large areas of the state. A number of field checks were made of these areas, but some were inaccessible due to remoteness and lack of access roads, or to exclusion by the U.S. Department of Defense from bombing ranges and proving grounds. All available information of these areas was culled from sources such as geologic, climatic and topographic maps as well as from general knowledge to describe their soil associations.

Most of the soil associations of the general soil map were named after the dominant soil series that compose them. Some associations were named using subgroup or great group category names including those of the alluvial floodplain soils, of the shallow, rocky soils on low desert mountains and of a few relatively inaccessible areas. A few units were named after both the soil series and subgroup class names. Some associations contain ‘‘not soils’’ in which case the name of a miscellaneous land area was used, rock outcrop, for instance.

Soil Taxonomy (Soil Survey Staff, 1975) prescribes grouping soils by the soil temperature zones in which they


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occur. Doing so produced four reasonable regions: hyperthermic, thermic, mesic and frigid. Then, the addition of precipitation zones arid, semiarid and subhumid produced three more reasonable units. When the soil units developed from the county general soil maps were modified and grouped into the temperature-precipitation zones, the result was a total of 64 soil associations in seven temperature-precipitation units (Table 4).

It is emphasized that the Arizona General Soil Map is not a guide for the user to specific soil uses in specific areas. This map is a broad guide to area planners engaged in general planning efforts. Proper use of this map is to select areas apparently suitable for specific uses for more detailed investigations. The final determination of suitability of a specific area for a specific use has to be determined by on-site investigations.

Reliability of the mapping units varies considerably. Descriptions of units identified by great group or subgroup names, such as HA1, TS2 and MA5, are very general. Descriptions of those soil associations in remote and inaccessible areas also have a low degree of reliability. Still, such descriptions may be useful for general planning purposes. Soil associations in areas previously described in detailed soil maps have a high degree of reliability for general soil map purposes. Examples of these units are HA2, HA3 and TS11.

7.2. Mapping Unit Descriptions

FIGURE 41. Explanation of Soil and Rock Symbols in Soilscapes and Profiles


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7.2.1. Hyperthermic Arid Soils

FIGURE 42. Representative Hyperthermic Arid Soils Soilscape and Profiles (D. M. Hendricks)


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FIGURE 43. Geographic Distribution of Hyperthermic Arid (HA) Soils in Arizona (D. M. Hendricks)

HA1 Torrifluvents Association
HA2 Casa Grande-Mohall-La Palma Association
HA3 Mohall-Vecont-Pinamt Association
HA4 Gunsight-Rillito-Pinal Association
HA5 Laveen-Rillito Association
HA6 Lithic Camborthids-Rock Outcrop-Lithic Haplargids Association
HA7 Laveen-Carrizo-Antho Association
HA8 Tremant-Coolidge-Mohall Association
HA9 Harqua-Perryville-Gunsight Association
HA10 Superstition-Rositas Association

HA Hyperthermic Arid Soils

Hyperthermic Arid Soils have mean annual soil temperatures of 22 C (72 F) or higher. The difference between mean summer and mean winter temperatures is greater than 5 C (9 F) at a depth of 50 cm (20 in) or at the soil-bedrock interface in shallow soils. These soils receive less than 250 mm (10 in) mean annual precipitation. Hyperthermic Arid Soils are at the lower elevations in western and southwestern Arizona. They cover about 8,198,860 ha (20,259,100 ac), 27 percent of Arizona.


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HA1 Torrifluvents Association

Deep, stratified, coarse to fine-textured, nearly level to gently sloping soils on floodplains and lower alluvial fans.

  • Soil Classification Typic Torrifluvents
  • Percent Slope none to 5
  • Elevation 30 to 760 m (100 to 2,500 ft)
  • Mean Annual Precipitation 80 to 250 mm (3 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 40 to 70
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 27 to 32 C (80 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 255 to 320
  • Area and Percent of State 1,928,400 ha (4,765,000 ac), 6.5
  • Land Uses irrigated cropland and pasture, rangeland and urban

This association consists of well-drained to somewhat excessively drained soils formed in sandy to clayey recent mixed alluvium on the floodplains and adjacent lower alluvial fans of the lower Santa Cruz, Gila, Salt and Colorado rivers and their major tributaries.

The major Torrifluvents in this map unit include Gilman soils, 20 percent; Antho soils, 20 percent; Vint soils, 15 percent; and Valencia soils, 15 percent. Other similar soils that may be dominant in some areas include Estrella, Avondale, Glenbar, Trix, Holtville, Kofa, Indio, Pimer, Laguna and Gadsden. They constitute about 20 percent of this association. Minor coarse-textured soils and medium and moderately fine-textured soils that are moderately deep over coarse-textured material are about 5 percent of this unit. Included are Carrizo, Brios, Agualt and Maripo and riverwash.

All of the soils in this association are subject to seasonal, brief flooding unless protected. Runoff is slow and the hazard of erosion is usually slight except along entrenched streams where soils are subject to bank cutting, piping and gullying.

About 30 percent of the major irrigated croplands in Arizona are in this association. The principal crops are cotton, grain sorghum, small grains, alfalfa, sugar beets, pasture grasses, vegetables and citrus.

Desert rangeland has low carrying capacity. The native vegetation is mesquite, catclaw, cresosotebush, cacti, bursage, ironwood, arrowweed, saltbush and annual grasses and weeds. Riparian vegetation along major streams includes cottonwood, paloverde, desertwillow and tamarisk, which provide shade for livestock and habitat for many desert wildlife species.

Phoenix and several towns and metropolitan areas are on these soils. Flooding potential is the major limitation of these soils. The permeability of the Valencia soil and the included Estrella, Avondale, Glenbar, Trix, Pimer and Gadsden soils is too limited for septic tank disposal fields. The excessive permeability of the Vint, Antho and included Carrizo, Brios, Agualt and Maripo soils prohibits their use for water retention structures.


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HA2 Casa Grande-Mohall-La Palma Association

Deep and moderately deep, moderately fine-textured, nearly level soils on valley plains.

  • Soil Classification
    • Typic Natrargids
    • Typic Haplargids
    • Typic Durargids
  • Percent Slope none to 2
  • Elevation 240 to 490 m (800 to 1,600 ft)
  • Mean Annual Precipitation 150 to 250 mm (6 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 250 to 300
  • Area and Percent of State 225,420 ha (557,000 ac), 0.8
  • Land Uses irrigated cropland, desert rangeland, wildlife habitat and building sites

This association of well-drained soils formed in mixed old alluvium is on valley plains and lower slopes.

Casa Grande soils make up about 35 percent of the map unit, Mohall soils 30 percent, La Palma soils 10 percent, Harqua soils 10 percent and minor soils 15 percent. The minor soils are mostly Tremant, Toltec, Vecont, Laveen and Gilman.

Low amounts of forage for livestock and wildlife are in this unit. The native vegetation is creosotebush, mesquite, paloverde, bursage, cacti and annual weeds and grasses. Supplemental grazing is provided in wet years by the annual grasses and forbs.

Most of the irrigated cropland is on Mohall soils and Casa Grande and Harqua soils that have been reclaimed by leaching. The principal crops are cotton, small grains, grain sorghum, alfalfa and pasture grasses.

Nonirrigated soils have low potential for use as rangeland wildlife habitat. Irrigated soils have good potential for use as openland wildlife habitat.

Factors limiting urban development on these soils are slow permeability, high lime zones in the subsoils, moderate depth to hardpan in La Palma soils, and high salinity and sodium in Casa Grande, La Palma and Harqua soils.


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HA3 Mohall-Vecont-Pinamt Association

Deep, moderately fine and fine-textured and gravelly, moderately fine-textured, nearly level to gently sloping soils on valley plains.

  • Soil Classification Typic Haplargids
  • Percent Slope mostly less than 2; some to 8
  • Elevation 240 to 760 m (800 to 2,500 ft)
  • Mean Annual Precipitation 150 to 280 mm (6 to 11 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 60
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 230 to 300
  • Area and Percent of State 350,070 ha (865,000 ac), 1.2
  • Land Uses desert rangeland and wildlife habitat; some irrigated cropland and homesites

This association of well-drained soils formed in mixed old alluvium on broad valley plains.

Mohall soils make up about 25 percent of the association. Vecont, Pinamt and Tremant soils each represent 20 percent, and minor soils 15 percent. The minor soils include small, intermixed areas of Laveen, Ebon, Contine and Rillito, and narrow bodies of Torrifluvents along the drainageways.

Most of the native vegetation is paloverde, mesquite, creosotebush, ironwood, cacti, bursage and annual weeds and grasses.

Low amounts of forage for livestock and wildlife grow in the unit. Supplemental grazing is provided in wet seasons by annual grasses and forbs.

Mohall soils are well suited for growing arid-adapted crops when irrigation water is available. Slow intake and permeability of Vecont soils require careful water management. Tremant and Pinamt soils usually are not cultivated.

Factors limiting the potential of these soils for homesites are the moderately slow or slow permeability for use as septic tank absorption fields, high shrink-swell in Vecont soils and moderate shrink-swell in Mohall and Tremant soils. The gravelly, high-lime substratum material of the Tremant and Pinamt soils is poor for use as topsoil or landfill cover.


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HA4 Gunsight-Rillito-Pinal Association

Deep and shallow, limy, gravelly, medium and moderately coarse-textured, nearly level to strongly sloping soils on alluvial surfaces and valley plains.

  • Soil Classification
    • Typic Calciorthids
    • Typic Durorthids
    • Typic Paleorthids
  • Percent Slope mostly none to 5; some to 15 or more
  • Elevation 120 to 760 m (400 to 2,400 ft)
  • Mean Annual Precipitation 100 to 250 mm (4 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 65
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 255 to 320
  • Area and Percent of State 832,470 ha (2,057,000 ac), 2.8
  • Land Uses mostly desert rangeland and wildlife habitat; some homesites

This association of well-drained soils is on broad, shallowly dissected alluvial fans and valley slopes. The soils formed in calcareous, old mixed alluvium derived from volcanic rocks, schist, limestone and granite.

Gunsight and Rillito soils each constitute about 30 percent of this association. Pinal soils cover about 15 percent, Cavelt soils 10 percent and other minor soil inclusions 15 percent. The principal minor soils are Ajo, Cipriano, Laveen, Perryville, Ligurta, Cristobal and Harqua along with small areas of rock outcrop and Torrifluvents in the drainageways. Areas of these soils are in the Organ Pipe National Monument.

The soils produce little forage for livestock and wildlife. Native vegetation consists of widely spaced paloverde, mesquite, cacti, creosotebush, bursage, ironwood, saltbush and annuals. Limited forage is provided by annual grasses and forbs following rainy periods. Larger vegetation along drainageways provides the best wildlife habitat.

Factors limiting these soils for homesite and community uses are high lime and excessive gravel contents. Shallow depth to hardpan and low water capacity in the Pinal and Cavelt soils restrict plant growth. Excavations require the use of heavy equipment in most places. The soils are fairly well suited to support for low buildings without basements. Gunsight and Rillito soils are suitable for use as septic tank absorption fields but have excessive seepage for use as water retention structures.


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HA5 Laveen-Rillito Association

Deep, medium and moderately coarse-textured, nearly level to gently sloping, limy soils on low alluvial surfaces and valley plains.

  • Soil Classification Typic Calciorthids
  • Percent Slope mostly none to 3
  • Elevation 180 to 550 m (600 to 1,800 ft)
  • Mean Annual Precipitation 130 to 250 mm (5 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 60 to 65
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 C)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 250 to 300
  • Area and Percent of State 179,080 ha (442,500 ac), 0.6
  • Land Uses irrigated cropland, desert rangeland, wildlife habitat and communities

This association of limy, well-drained soils formed in calcareous, old alluvium derived from limestone and other rocks.

Laveen soils make up about 40 percent of the association, Rillito soils 35 percent and minor soils 25 percent. The minor soils are mostly Mohall, Coolidge, Tremant, Perryville, Antho and Gilman.

Irrigated Laveen soils have good and Rillito soils have fair potential for cropland use. Crops are alfalfa, cotton, small grains, grain sorghum, safflower and sugar beets. Lime sensitive plants may show some chlorosis on these soils. Rillito soils require more frequent irrigation due to lower available water capacity.

Nonirrigated areas produce limited forage for livestock and wildlife. Native vegetation consists of sparse stands of creosotebush, saltbush, bursage, mesquite, paloverde, ironwood, cacti and annual weeds, forbs and grasses. Annuals that grow following rainy periods provide supplemental seasonal grazing.

Where irrigated, these soils are good openland wildlife habitat for doves, quail, rabbits, songbirds, rodents, foxes, badgers, coyotes and snakes.

The soils in this association generally have only slight limitations for most community uses such as homesites, septic tank absorption fields, sanitary landfill and excavations. They are somewhat dusty for use as playgrounds, camping sites and picnic areas. Water retention structures such as sewage lagoons and earthen ponds may seep excessively. Substratum materials may cause chlorosis in plants if used as topsoil.


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HA6 Lithic Camborthids-Rock Outcrop-Lithic Haplargids Association

Shallow, very gravelly and cobbly, moderately coarse to moderately fine-textured, gently sloping to very steep soils and rock outcrop on hills and mountains.

  • Soil Classification
    • Lithic Camborthids
    • Typic Durorthids
    • Lithic Haplargids
  • Percent Slope 2 to 60 or more
  • Elevation 90 to 1,490 m (300 to 4,900 ft)
  • Mean Annual Precipitation 100 to 250 mm (4 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 65
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 250 to 300
  • Area and Percent of State 3,094,130 ha (7,645,500 ac), 10.5
  • Land Uses desert rangeland, wildlife habitat, game refuge, military proving grounds and bombing range and recreation; also heavy equipment proving grounds and city and county parks

This association consists of well-drained, shallow soils and rock outcrop on hills and low mountains. The soils formed in materials weathered residually from granitic rocks, schists, volcanic tuffs and conglomerates, basalt and some shale and sandstone.

Lithic Camborthids make up about 20 percent of the association, Typic Durorthids 15 percent, rock outcrop 35 percent, Lithic Haplargids 15 percent and minor soils 15 percent. Lomitas soils are representative of the Lithic Camborthids. Cherioni soils are the dominant Lithic Durorthids and Gachado soils the Lithic Haplargids. The minor soils are mostly Gunsight, Harqua, Rillito, Ligurta, Cristobal and Pinamt. Torrifluvents and Torriorthents are along drainageways.

Rock outcrop tops the mountain ranges as near-vertical ledges, escarpments and pinnacles, and occurs scattered throughout the shallow soils at the lower elevations.

Dominant native vegetation is creosotebush, paloverde, ironwood, ocotillo, bursage, jojoba, range ratany, saguaro and other cacti, bush muhly, big galleta, tridens, Rothrock and black grama, fluffgrass and annuals.

These soils accommodate little livestock grazing due to rockiness and steepness of the terrain and too low rainfall. Parts of the unit are prime habitat for bighorn sheep.

Factors limiting these soils for homesite and other community uses are shallow depth to rock and slopes of more than 8 percent. Rock fragments on the surface limit use for playgrounds, campgrounds and picnic areas. However, some smoother areas can be used for these purposes or the loose rocks may be removed in others. Many areas, such as the Ajo Mountains, are scenic and unique.


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HA7 Laveen-Carrizo-Antho Association

Deep, medium-textured, limy and gravelly, moderately coarse and coarse-textured, nearly level to moderately sloping soils on floodplains and dissected alluvial surfaces.

  • Soil Classification
    • Typic Calciorthids
    • Typic Torriorthents
    • Typic Torrifluvents
  • Percent Slope mostly none to 8; some steep slopes
  • Elevation 150 to 610 m (500 to 2,000 ft)
  • Mean Annual Precipitation 100 to 200 mm (4 to 8 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 65 to 70
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 250 to 300
  • Area and Percent of State 154,390 ha (381,500 ac), 0.5
  • Land Uses rangeland, wildlife habitat, homesites and recreation

This association consists of well-drained and excessively drained soils on dissected old alluvial fans and sandy floodplains. They formed in transported alluvium derived from mixed igneous and sedimentary rocks.

Laveen soils make up about 30 percent of this association, Carrizo soils 25 percent, Antho soils 25 percent and minor soils 20 percent. The minor soils are mostly Rillito, Laguna, Brios, Vint, Gilman, Ligurta, Cristobal and Cavelt, and riverwash.

The native vegetation is a sparse growth of creosotebush, bursage, paloverde, catclaw, filaree, cacti, threeawn and annual weeds and grasses.

These soils produce little forage for livestock and wildlife. Seasonal grazing is possible for short periods following rainy periods. Riparian vegetation along some drainageways furnishes cover and some food for wildlife.

Laveen and Antho soils are good for homesite and other community uses, if protected from flooding. They may be somewhat dusty for use as playgrounds and campgrounds. Carrizo soils have very rapid permeability. They are subject to flooding and excessive seepage prohibits their use for sanitary facilities. They are good potential sources of sand and gravel.


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HA8 Tremant-Coolidge-Mohall Association

Deep, moderately coarse and gravelly, moderately fine-textured, nearly level and gently sloping soils on low fan surfaces and valley plains.

  • Soil Classification
    • Typic Haplargids
    • Typic Calciorthids
  • Percent Slope mostly none to 2; some to 5
  • Elevation 120 to 760 m (400 to 2,500 ft)
  • Mean Annual Precipitation 80 to 250 mm (3 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 65
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 250 to 300
  • Area and Percent of State 890,340 ha (2,200,000 ac), 3.0
  • Land Uses desert rangeland, wildlife habitat, irrigated cropland, homesites and military reservations

This association consists of well-drained soils in broad valleys and adjacent lower alluvial fans. The soils formed in old mixed alluvium derived from igneous and calcareous sedimentary rocks.

Tremant soils make up about 40 percent of this association, Coolidge soils 15 percent, Laveen soils 15 percent and Mohall soils 15 percent. Included in the mapping unit are large areas of Valencia, Rillito and Pinamt soils. Also included in the unit are a few low hills and mountains that have rocky, shallow soils and areas of moderately coarse-textured recent stratified alluvial soils in drainageways. The minor soils make up about 15 percent of the association.

Nonirrigated areas provide some forage for livestock and wildlife. The vegetation consists of creosotebush, scattered paloverde, mesquite and ironwood, saltbush, bursage, cacti and annuals. Limited grazing of annual grasses is possible following wet seasons. Wildlife habitat is mostly along drainageways.

Only small areas are irrigated cropland. They produce alfalfa, small grain, grain sorghum and other arid-adapted crops. Tremant and Coolidge soils are somewhat droughty.

Factors limiting these soils for homesite and community uses are the moderately slow permeability and moderate shrink-swell of the Tremant and Mohall soils. Laveen and Coolidge soils generally are well suited for building sites and sanitary facilities. The limy substrata of all of these soils are poor for topsoil and landfill cover. Denuded areas are dusty.


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HA9 Harqua-Perryville-Gunsight Association

Deep, gravelly, moderately fine-textured, and gravelly, limy, medium-textured, nearly level to moderately sloping soils on old fan surfaces.

  • Soil Classification
    • Typic Haplargids
    • Typic Calciorthids
  • Percent Slope mostly 1 to 8; some to 15
  • Elevation 90 to 460 m (300 to 1,500 ft)
  • Mean Annual Precipitation 80 to 200 mm (3 to 8 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 65
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 22 to 27 C (72 to 80 F)
  • Frost-Free Days 250 to 300
  • Area and Percent of State 394,180 ha (974,000 ac), 1.3
  • Land Uses wildlife habitat and military proving grounds; some livestock grazing and building sites

This association consists of well-drained, gravelly soils in broad intermountain valleys. They formed in old alluvium derived from volcanic and calcareous sedimentary rocks. Many areas are saline and sodic.

Harqua soils make up about 35 percent of the mapping unit, Perryville soils 25 percent, Gunsight soils 20 percent and minor soils 20 percent. The minor soils are mostly Coolidge, Rillito, Ligurta and Cristobal and small, rocky areas of Lomitas and Cherioni.

Parts of the unit are in the Kofa and Cibola National Wildlife refuges. The dominant native vegetation is a sparse cover of creosotebush, saltbush, bursage, cholla and other cacti, and annual grasses and weeds.

The major limitations of these soils for community uses are moderate to high gravel content of all soils, high salt and alkali content and moderate shrink-swell in Harqua soils and high lime content of the Perryville and Gunsight soils. Perryville and Gunsight soils are suitable sites for low buildings and local roads, and for use as roadfill. The soils are poor for topsoil due to high lime and gravel content. Dust may be a problem in denuded and disturbed areas.


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HA10 Superstition-Rosita Association

Deep, coarse-textured, nearly level and undulating soils on terraces.

  • Soil Classification
    • Typic Calciorthids
    • Typic Torripsamments
  • Percent Slope mostly none to 2; some to 15
  • Elevation 30 to 305 m (100 to 1,000 ft)
  • Mean Annual Precipitation 80 to 150 mm (3 to 6 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 60 to 65
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 23 to 26 C (74 to 79 F)
  • Frost-Free Days 280 to 320
  • Area and Percent of State 150,390 ha (371,600 ac), 0.5
  • Land Uses irrigated cropland, urban and military

This association consists of somewhat excessively drained soils.

Superstition soils make up about 60 percent of the association and Rositas soils 20 percent. The remaining 20 percent includes intermixed areas of Coolidge, Rillito and Harqua soils and a few small areas of rocky buttes and sand dunes.

The natural vegetation consists of widely spaced creosotebush, big galleta, white bursage, turkshead and annual grasses and forbs.

The irrigated crops grown are mostly alfalfa, citrus and a few dates. Numerous frequent irrigations are required for these crops and much of the water applied percolates to the aquifer. Where they are used, new methods of irrigation such as drip or bubbler irrigation have reduced water losses. Cover crops and windbreaks usually are necessary while establishing crops to prevent soil loss by wind erosion.

Factors limiting the potential of these soils for community uses are droughtiness, blowing soil, excessive seepage, loose sandy surfaces and soil caving in excavations. These limitations can be partially overcome by special measures such as windbreaks, drip irrigation and soil stabilization.


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7.2.2. Thermic Arid Soils

FIGURE 44. Representative Thermic Arid Soils Soilscape and Profiles (D. M. Hendricks)


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FIGURE 45. Geographic Distribution of Thermic Arid (TA) Soils in Arizona (D. M. Hendricks)

TA1 Torriorthents-Camborthids-Rock Outcrop Association
TA2 Anthony-Vinton-Agua Association
TA3 Lithic Torriorthents-Rock Outcrop-Lithic Haplargids Association
TA4 Latene-Anthony-Tres Hermanos Association
TA5 Paleorthids-Calciorthids-Torriorthents Association

TA Thermic Arid Soils

Thermic Arid Soils have mean annual soil temperatures of 15 to 22 C (59 to 72 F). The difference between mean summer and mean winter temperatures is greater than 5 C (9 F) at 50 cm (20 in) or at the soil-bedrock interface in shallow soils. The mean annual precipitation associated with these soils falls between 130 to 250 mm (5 to 10 in). These soils are primarily at low to intermediate elevations in northwestern Arizona as well as along and in the Grand Canyon. Thermic Arid Soils cover about 2,263,240 ha (5,592,400 ac), or 8 percent of Arizona.


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TA1 Tottiorthents-Camborthids-Rock Our-Crop Association

Shallow and moderately deep soils and rock outcrop of the canyons, cliffs and mesas.

  • Soil Classification
    • Torriorthents
    • Camborthids
  • Percent Slope 5 to vertical, some to 1,820 m (6,000 ft)
  • Elevation 360 to 2,430 m (1,200 to 8,000 ft)
  • Mean Annual Precipitation mostly 150 to 250 mm (6 to 10 in); range is 150 to 500 mm (6 to 20 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 60 to 65
  • Mean January Air Temperature -1 to 7 C (30 to 45 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature mostly 15 to 22 C (59 to 72 F); range is 8 10 24 C (47 to 75 F)
  • Frost-Free Days 90 to 340
  • Area and Percent of State 779,690 ha (1,926,600 ac), 2.7
  • Land Uses recreation, wildlife habitat and some cropland

This association consists primarily of the Grand Canyon area and the major tributaries to the Colorado River. These are shallow and moderately deep, moderately sloping to extremely steep, gravelly, cobbly and stony, moderately coarse to moderately fine-textured soils developed in colluvial and on residual materials such as limestone, sandstone and shale bedrock.

Torriorthents make up about 65 percent of this association, Camborthids about 15 percent and rock outcrop about 15 percent. About 5 percent of the mapping unit is Ustorthents, recent alluvial soils along the tributary drainageways and the Colorado River, very steep talus materials and water, including the Colorado River and the Arizona portions of Lake Mead and Lake Powell.

The contrasting hues of reds, grays and whites and the vastness of the relief formed by millions of years of geologic erosion make this area one of unparalleled scenic grandeur. Recreation activities include hiking, camping, boating and fishing. Most of the area is in the Lake Mead National Recreational Area and the Grand Canyon National Monument, both administered by the National Park Service. Several campgrounds and resorts are in the area. The Havasupai Indians farm a small area near the bottom of the Grand Canyon. Vegetation ranges from desert shrubs in the hot, arid inner canyon to juniper and pine at the higher elevations.

Factors limiting the potential of these soils for development of homesites or campgrounds are the shallow depths to bedrock and the steep slopes.


[page 88]

TA2 Anthony-Vinton-Agua Association

Deep, medium to coarse-textured, nearly level to gently sloping soils on floodplains and low alluvial fans.

  • Soil Classification Typic Torrifluvents
  • Percent Slope none to 5
  • Elevation 610 to 1,220 m (2,000 to 4,000 ft)
  • Mean Annual Precipitation 130 to 250 mm (5 to 10 in)
  • Winter Precipitation as the Percentage of Annual Percipitation 60 to 70
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 15 to 22 C (59 to 72 F)
  • Frost-Free Days 200 to 275
  • Area and Percent of State 448,210 ha (1,107,500 ac), 1.5
  • Land Uses rangeland, wildlife habitat and homesites; some irrigated cropland and pasture along Big Sandy River

This association consists of well-drained soils on the floodplains of intermountain valleys. The soils formed in recent mixed alluvium derived from granite and other rocks.

Anthony soils make up about 35 percent of the association, Vinton soils 30 percent and Agua soils 20 percent. Included in the mapping unit are Gila, Glendale, Tobler and Harrisburg soils in drainageways, and small areas of Rillito and Nickel on low fan surfaces. These minor soils make up about 15 percent of the unit.

All of these soils are subject to brief flooding during wet seasons unless protected.

Vegetation is creosotebush, paloverde, mesquite, cacti, catclaw and annual grasses and weeds. Joshua trees grow north of Red Lake and cottonwood and tamarisk grow along Big Sandy River.

The rangeland generally has low carrying capacity due to the low rainfall and the dominance of low-palatability brushy species. Areas that receive runoff from adjacent uplands support vegetation for seasonal grazing. Riparian vegetation along major streams provides good habitat for various wildlife species.

Possible flooding is a severe limitation for homesite and many other community uses. If protected from flooding, these soils are suitable for use as homesites and sanitary facilities. Excessive seepage, however, prohibits their use for water impoundment structures. These soils are somewhat droughty for growing lawns and landscape plants.


[page 89]

TA3 Lithic Torriorthents-Rock Outcrop-Lithic Haplargids Association

Shallow, gravelly and cobbly, moderately sloping to very steep soils and rock outcrop on hills and mountains.

  • Soil Classification
    • Lithic Torriorthents
    • Lithic Haplargids
  • Percent Slope mostly 30 to 50; range is 5 to 70 or more
  • Elevation 670 to 1,730 m (2,200 to 5,700 ft)
  • Mean Annual Precipitation 130 to 250 mm (5 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 60 to 70
  • Mean January Air Temperature 2 to 10 C (35 to 50 F)
  • Mean July Air Temperature 18 to 32 C (65 to 90 F)
  • Mean Annual Soil Temperature 17 to 22 C (62 to 72 F)
  • Frost-Free Days 200 to 275
  • Area and Percent of State 443,510 ha (1,095,900 ac), 1.5
  • Land Uses rangeland, wildlife habitat and recreation; some building sites and mines

This association consists of well-drained, shallow soils and rock outcrop on hills and low mountains in hot, arid areas. The soils formed in residuum weathered from granite, gneiss, schist and volcanic rocks, including tuffs.

Lithic Torriorthents (Cellar and House Mountain soils) make up about 35 percent of the association, rock outcrop 30 percent, Lithic Haplargids (Chiricahua and Lehmans soils) 20 percent and minor soils 15 percent. The minor soils are mostly small areas of Lampshire, Moano, Continental, Pinaleno and Tres Hermanos, and narrow bands of moderately coarse and coarse-textured, stratified soils along drainageways.

Dominant native vegetation is paloverde, mesquite, creosotebush, ocotillo, blackbrush, cacti, threeawn, galleta, bush muhly and blue, slender, sideoats and black grama.

Steepness and stoniness of the soils in this association limit livestock grazing to the smoother, less sloping areas. White- and blacktail deer and bighorn sheep are the primary big-game animals of these areas.

Most homesites and recreation areas are on soils adjacent to Lake Mead. The major soils of the association are severely limited for use as building sites due to excessive slopes and shallowness to bedrock. Chiricahua and Lehmans soils also have high shrink-swell.


[page 90]

TA4 Latene-Anthony-Tres Hermanos Association

Deep, moderately coarse to moderately fine-textured, nearly level to moderately steep soils on alluvial fan surfaces and valley plains.

  • Soil Classification
    • Typic Calciorthids
    • Typic Torrifluvents
    • Typic Haplargids
  • Percent Slope mostly none to 15; some to 30
  • Elevation 610 to 1,060 m (2,000 to 3,500 ft)
  • Mean Annual Precipitation 150 to 250 mm (6 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 60 to 65
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 17 to 22 C (62 to 72 F)
  • Frost-Free Days 210 to 275
  • Area and Percent of State 340,270 ha (840,800 ac), 1.2
  • Land Uses rangeland and wildlife habitat; some homesites and irrigated cropland

This association consists of well-drained soils on old alluvial fans and valley plains. They formed in mixed alluvium from igneous and calcareous sedimentary rocks.

Latene and Anthony soils each constitute about 30 percent of this association and Tres Hermanos soils 20 percent. Small areas of Cave, Continental, Gila, Mohave, Nickel, Pinaleno and Whitlock soils make up about 20 percent of the mapping unit.

Most of the native vegetation is bursage, creosotebush, galleta, snakeweed, paloverde, cacti and annual grasses and forbs. Forage production is low due to limited rainfall, but annual grasses and forbs provide some grazing following wet seasons. The best wildlife habitat is along drainageways.

These soils have fair to good potential for use as homesites if the following limitations are overcome: Anthony soils are subject to flooding and are moderately droughty; Latene and Tres Hermanos soils have high lime content on the substrate that is poor for topsoil; and some areas of Tres Hermanos soils have excessive slope.


[page 91]

TA5 Paleorthids-Calciorthids-Torriorthents Association

Shallow and deep, gravelly, medium to coarse-textured, limy, gently sloping to moderately steep soils on valley slopes and hills.

  • Soil Classification
    • Paleorthids
    • Calciorthids
    • Torriorthents
  • Percent Slope 1 to 30; a few near-vertical escarpments
  • Elevation 610 to 1,220 m (2,000 to 4,000 ft)
  • Mean Annual Precipitation 150 to 300 mm (6 to 12 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 60 to 70
  • Mean January Air Temperature 2 to 10 C (35 to 50 F)
  • Mean July Air Temperature 24 to 32 C (75 to 90 F)
  • Mean Annual Soil Temperature 15 to 22 C (59 to 72 F)
  • Frost-Free Days 200 to 275
  • Area and Percent of State 251,560 ha (621,600 ac), 0.9
  • Land Uses rangeland and wildlife habitat; some homesites and recreation near Lake Mead and irrigated cropland along Virgin River

This association consists of well-drained, calcareous soils on valley slopes, mesas and ridges. The soils formed in calcareous, gravelly alluvium derived from sedimentary and volcanic rocks.

Paleorthids make up about 30 percent of the association, Calciorthids 30 percent, Torriorthents 15 percent and minor soils 25 percent. Cave and Morman Mesa soils are the dominant Paleorthids, Nickel the dominant Calciorthid and Arizo the dominant Torriorthent. The minor soils include Arado, Winkel, Tonopah, Flattop, Bitter Spring, Moapa and St. Thomas. Also included are small areas of rock outcrop and narrow bodies of Torrifluvents along drainageways.

The native vegetation is mostly a sparse cover of creosotebush, blackbrush, bursage, Mormon-tea, desert almond, big galleta, Indian ricegrass, cacti, Mohave yucca and annual grasses and forbs.

These soils have low potential for forage production due to low rainfall and shallow soils. The best wildlife habitat is along drainageways.

Factors limiting the potential for use as homesites are shallow depths of the Paleorthids; high lime content of the Paleorthids and Calciorthids; and flooding hazard and droughtiness of the Torriorthents.


[page 92]

7.2.3. Thermic Semiarid Soils

FIGURE 46. Representative Thermic Semiarid Soils Soilscape and Profiles (D. M. Hendricks)


[page 93]

FIGURE 47. Geographic Distribution of Thermic Semiarid (TS) Soils in Arizona (D. M. Hendricks)

TS1 Torrifluvents-Torripsamments Association
TS2 Torrifluvents Association
TS3 Tubac-Sonoita-Grabe Association
TS4 White House-Bernardino-Hathaway Association
TS5 Caralampi-Hathaway Association
TS6 Lithic Torriorthents-Lithic Haplustolls-Rock Outcrop Association
TS7 White House-Caralampi Association
TS8 Caralampi-White House Association
TS9 Latene-Nickel-Pinaleno Association
TS10 Chiricahua-Cellar Association
TS11 Gothard-Crot-Stewart Association
TS12 Continental-Latene-Pinaleno Association
TS13 Karro-Gothard Association
TS14 Nickel-Latene-Cave Association
TS15 Bonita-Graham-Rimrock Association
TS16 Penthouse-Latene-Cornville Association
TS17 Signal-Grabe Association
TS18 Graham-Lampshire-House Mountain Association
TS19 Anthony-Sonoita Association

TS Thermic Semiarid Soils

Thermic Semiarid Soils have mean annual soil temperatures of 15 to 22 C (59 to 72 F). The difference between mean summer and mean winter temperatures is greater than 5 C (9 F) at a depth of 50 cm (20 in) or in shallow soils at the soil-bedrock interface. These soils receive 250 to 410 mm (10 to 16 in) annual precipitation. Elevations of Thermic Semiarid Soils range from low to intermediate. They cover about 5,966,410 ha (14,742,800 ac), or 20 percent of Arizona.


[page 94]

TS1 Torrifluvents-Torripsamments Association

Deep, moderately coarse and coarse-textured, nearly level to strongly sloping soils on floodplains and low alluvial fans.

  • Soil Classification
    • Torrifluvents
    • Torripsamments
  • Percent Slope none to 5
  • Elevation 1,030 to 1,220 m (3,400 to 4,000 ft)
  • Mean Annual Precipitation 200 to 300 mm (8 to 12 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 40 to 45
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 27 to 29 C (80 to 85 F)
  • Mean Annual Soil Temperature 16 to 21 C (61 to 69 F)
  • Frost-Free Days 210 to 250
  • Area and Percent of State 19,830 ha (49,000 ac), less than 0.1
  • Land Uses rangeland and wildlife habitat

This association consists of well-drained and somewhat excessively drained soils on floodplains and alluvial fans. They formed in recent sandy alluvium derived from igneous and sedimentary rocks.

Coarse, loamy Torrifluvents make up about 40 percent of the association, Torripsamments 40 percent and other fine, loamy Torrifluvents and sandy or gravelly Torriorthents 20 percent.

The vegetation is low-growing, scattered mesquite, saltbush, creosotebush, Mohave yucca, bush muhly, sand dropseed, blue and Rothrock grama and annual grasses and forbs.

The soils have low potential for forage production due to low rainfall and droughtiness of the soils. Many grasses and forbs, however, respond rapidly to any precipitation that falls during the growing season. Care should be taken to avoid overgrazing or disturbing these soils due to creating the hazard of blowing soil.

Factors limiting the potential of these soils for development of homesites are the flood hazards of the Torrifluvents and the very sandy texture of the Torripsamments.


[page 95]

TS2 Torrifluvents Association

Deep, moderately coarse to moderately fine-textured, nearly level to gently sloping soils on floodplains and alluvial fans.

  • Soil Classification Typic Torrifluvents
  • Percent Slope none to 3
  • Elevation 670 to 1,220 m (2,200 to 4,000 ft)
  • Mean Annual Precipitation 230 to 300 mm (9 to 12 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 40 to 50
  • Mean January Air Temperature 4 to 10 C (40 to 50 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 16 to 22 C (60 to 72 F)
  • Frost-Free Days 200 to 270
  • Area and Percent of State 142,860 ha (353,000 ac), 0.5
  • Land Uses irrigated cropland, rangeland, wildlife habitat, urban and recreation

This association consists of well-drained soils formed on recent mixed alluvium on the floodplains of the Santa Cruz, Upper Gila and San Pedro rivers and their tributaries.

Torrifluvents make up about 95 percent of this association and Torriorthents and other soils make up about 5 percent. The major Torrifluvents in this unit are Grabe, Pima and Anthony soils, each of which make up about 25 percent. About 20 percent consists of Comoro, Gila, Vinton, Guest and Glendale soils. Torriorthents and other included soils are mostly Arizo and Brazito soils and riverwash. Any of these soils may be dominant at a given site.

All of these soils are subject to flooding unless protected. Flooding is usually very brief and local. Areas along entrenched streams are subject to soil piping, gullying and bank cutting.

Cropland and community uses in this association require protection from flooding. Irrigated crops include cotton, alfalfa, grain sorghum, small grains, vegetables and pecans. Natural vegetation includes mesquite, saltbush, catclaw, creosotebush, arrowweed, desertwillow, bush muhly, Arizona cottontop, threeawn and annuals. These soils have medium potential for use as rangeland under good management. They have high potential for openland wildlife habitat in irrigated areas and fair potential for rangeland wildlife habitat where nonirrigated.


[page 96]

TS3 Tubac-Sonoita-Grabe Association

Deep, moderately coarse to fine-textured, nearly level to strongly sloping soils of the uplands and drainageways.

  • Soil Classification
    • Typic Paleargids
    • Typic Haplargids
  • Percent Slope mostly none to 8; some to 15
  • Elevation 910 to 1,520 m (3,000 to 5,000 ft)
  • Mean Annual Precipitation 250 to 400 mm (10 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 40 to 50
  • Mean January Air Temperature 4 to 10 C (40 to 50 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 16 to 22 C (61 to 72 F)
  • Frost-Free Days 185 to 265
  • Area and Percent of State 736,550 ha (1,820,000 ac), 2.5
  • Land Uses rangeland, wildlife habitat, irrigated cropland and some urban

This association consists of well-drained soils on valley plains and wide floodplains in the Santa Cruz, Sulphur Springs and San Simon valleys. The soils formed in mixed old and recent alluvium derived mostly from igneous rocks.

Tubac and the similar Continental soils make up about 50 percent of the association, Sonoita soils 20 percent, Grabe soils 20 percent and minor soils about 10 percent. The minor soils include Comoro, Pima, Guest, Anthony, Pinaleno, Eba, Forrest, McAllister, Anway, Tres Hermanos and Nickel.

Good yields of cotton, grain sorghum, alfalfa, small grain and vegetables are produced when the soils of this association are irrigated. The native vegetation is mostly grass in the higher elevations and desert shrubs and cacti at the lower elevations. Principal grasses are gramas, plains lovegrass, tobosa and annuals. Shrubs are mesquite, whitethorn, catclaw, burroweed, wolfberry and cacti. Paloverde and ironwood occur at lower elevations.

Under good range management, these soils have fair to good potential for the production of livestock forage. Many areas are in poor condition from overgrazing due to their easy accessibility.

Factors limiting the potential of these areas for development of homesites and other community uses are slow permeability and clayey subsoils in the Tubac and Continental soils and the possibility of flooding of Grabe soils. Sonoita soils are well suited for community uses.


[page 97]

TS4 White House-Bernardino-Hathaway Association

Deep, fine-textured and gravelly, moderately coarse to moderately fine-textured, nearly level to moderately steep soils on alluvial fan surfaces and steep side slopes.

  • Soil Classification
    • Ustollic Haplargids
    • Aridic Calciustolls
  • Percent Slope mostly 1 to 20, but to 50 where Hathaway soils occur
  • Elevation 1,030 to 1,550 m (3,400 to 5,100 ft)
  • Mean Annual Precipitation 300 to 460 mm (12 to 18 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature 2 to 7 C (35 to 45 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 15 to 21 C (59 to 70 F)
  • Frost-Free Days 160 to 250
  • Area and Percent of State 326,920 ha (807,800 ac), 1.1
  • Land Uses rangeland, wildlife habitat and some homesites

This association consists of well-drained soils on nearly level to hilly valley plains and dissected old terraces. The soils formed in old alluvium derived from granitic, volcanic and sedimentary rocks.

White House soils make up about 40 percent of the association, Bernardino soils 20 percent, Hathaway soils 20 percent and minor soils 20 percent. The minor soils are mostly Caralampi and small areas of Bonita, Nickel, Pinaleno and Chiricahua and rock outcrop. Narrow bodies of Guest and Pima soil are along drainageways.

The dominant native vegetation is plains lovegrass, beargrass and blue, black, hairy, sideoats and slender grama. Scattered mesquite and cacti, with some oak trees, grow at higher elevations.

This association has some of the best rangeland in the state, and the potential for range improvement is high. It has fair potential for rangeland wildlife habitat.

Factors limiting the potential of the soils for community uses are slow permeability and high shrink-swell in the White House and Bernardino soils and excessive slope and high lime in Hathaway and some Bernardino soils.


[page 98]

TS5 Caralampi-Hathaway Association

Deep, gravelly, moderately coarse to moderately fine-textured, moderately steep to very steep soils on highly dissected old fan surfaces.

  • Soil Classification
    • Ustollic Haplargids
    • Aridic Calciustolls
  • Percent Slope mostly 20 to 60; range is 10 to 70
  • Elevation 910 to 1,520 m (3,000 to 5,000 ft)
  • Mean Annual Precipitation 300 to 410 mm (12 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 35 to 45
  • Mean January Air Temperature 4 to 10 C (40 to 45 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature 16 to 21 C (60 to 70 F)
  • Frost-Free Days 170 to 250
  • Area and Percent of State 203,360 ha (502,500 ac), 0.7
  • Land Uses rangeland and wildlife habitat; some homesites near Nogales

This association consists of well-drained, very gravelly soils on long narrow ridges formed by deep dissection of old fan surfaces. The soils formed in old alluvium derived from igneous and sedimentary rocks.

Caralampi soils make up about 45 percent of the association, Hathaway soils 35 percent and minor soils about 20 percent. The minor soils include White House, Bernardino, Nolam and Signal on uplands and narrow bands of Torrifluvents and Torriorthents along drainageways. The minor soils may be extensive in some areas.

The dominant native vegetation is plains lovegrass, cane and Texas bluestem, calliandra, beargrass, sideoats, blue, black, hairy and slender grama, and scattered mesquite and cacti. Some oak and juniper grow at higher elevations.

Slopes in excess of 30 percent are somewhat steep for grazing by cattle and horses. The good wildlife habitat is provided in drainageways.

The major factors limiting the potential of these soils for community uses are slopes in excess of 15 percent and high gravel content. Hathaway soils are high in lime.


[page 99]

TS6 Lithic Torriorthents-Lithic Haplustolls-Rock Outcrop Association

Shallow, cobbly and gravelly, strongly sloping to very steep soils and rock outcrop on hills and mountains.

  • Soil Classification
    • Lithic Torriorthents
    • Lithic Haplustolls
  • Percent Slope mostly 20 to 50; range is 10 to 70
  • Elevation 760 to 1,760 m (2,500 to 5,800 ft)
  • Mean Annual Precipitation 250 to 510 mm (10 to 20 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 35 to 60
  • Mean January Air Temperature 2 to 10 C (35 to 50 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 15 to 22 C (59 to 72 F)
  • Frost-Free Days 160 to 260
  • Area and Percent of State 2,040,090 ha (5,041,000 ac), 6.9
  • Land Uses wildlife habitat, rangeland, recreation and mining of copper lead, zinc, silver and gold

This association consists of well-drained, shallow soils and rock outcrop on semiarid, mid-elevation hills and mountains. The soils formed in residuum weathered from many rocks including granite, gneiss, rhyolite, andesite, tuffs, limestone, sandstone and basalt.

Lithic Torriorthents make up about 30 percent of the association, Lithic Haplustolls 25 percent, rock outcrop about 25 percent and Haplargids, other minor soils and Torrifluvents along drainageways, about 20 percent.

The Lithic Torriorthents include House Mountain, Cellar, Retriever, Courthouse, St. Thomas and Schrap series. The Lithic Haplustolls include Lampshire and Mabray soils and similar soils such as Atascosa and Romero. The dominant included Haplargids are Anklam, Chiminea, Chiricahua, Lehmans, Graham, Deloro and Oracle. Other minor soils include Pantano, Pinaleno, Caralampi and Nickel.

Parker Canyon, Arivaipa, Pena Blanca and Patagonia lakes are within areas bounded by this association. The native vegetation varies with elevation and precipitation. At lower elevations the dominant vegetation is paloverde, mesquite, whitethorn, catclaw, jojoba, calliandra, saguaro and other cacti and some grasses. At higher elevations grow many more perennial grasses including Arizona cottontop, cane and Texas bluestem, plains lovegrass, green sprangletop, wolftail and blue, hairy, black, sideoats and slender grama and many others. Oak and juniper may grow above 1,220 m (4,000 ft), but paloverde and saguaro do not grow at this elevation.

Smoother areas of this association have good potential for livestock grazing. The steeper, stonier areas are little used by domestic livestock, but they are good habitat for deer and, in some areas, bighorn sheep.

Factors limiting the potential of these areas for community uses are steep slopes, shallow depth to bedrock and rock fragments on the surface. Selected areas are suitable for campgrounds, picnic areas and pack trails.


[page 100]

TS7 White House-Caralampi Association

Deep, fine-textured and gravelly, moderately fine-textured, gently to moderately sloping soils on old alluvial fan surfaces.

  • Soil Classification Ustollic Haplargids
  • Percent Slope mostly 2 to 8; some to 15
  • Elevation 760 to 1,340 m (2,500 to 4,400 ft)
  • Mean Annual Precipitation 300 to 410 mm (12 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 60
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 18 to 21 C (64 to 70 F)
  • Frost-Free Days 240 to 270
  • Area and Percent of State 67,180 ha (166,000 ac), 0.2
  • Land Uses rangeland and wildlife habitat; some homesites

This association consists of well-drained soils on old alluvial fan surfaces. They formed in old mixed alluvium weathered mostly from granitic and sedimentary rocks.

White House soils make up about 50 percent of the association, Caralampi soils 35 percent and minor soils 15 percent. The minor soils include small areas of Hathaway, Nolam, Bernardino and Palos Verdes and narrow bands of Torrifluvents along drainageways.

The dominant native vegetation is grama grasses, plains lovegrass, bush muhly, threeawn, calliandra, mesquite, cacti, burroweed and annual grasses and forbs.

Under good management, the soils have fair to good potential for the production of range forage. Good wildlife habitat is along drainageways.

Factors limiting the potential of these areas for homesite development are high shrink-swell and slow permeability in White House soils and high gravel content in Caralampi soils.


[page 101]

TS8 Caralampi-White House Association

Deep, gravelly, moderately fine and fine-textured, moderately sloping to steep soils on dissected old alluvial fan surfaces.

  • Soil Classification Ustollic Haplargids
  • Percent Slope 5 to 30
  • Elevation 700 to 1,220 m (2,300 to 4,000 ft)
  • Mean Annual Precipitation 300 to 410 mm (12 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 60
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 18 to 21 C (65 to 70 F)
  • Frost-Free Days 200 to 270
  • Area and Percent of State 102,390 ha (253,000 ac), 0.3
  • Land Uses rangeland and wildlife habitat; some building sites

This association consists of well-drained soils on dissected old alluvial fans adjacent to the San Pedro River. The soils formed in old alluvium derived from granite and sedimentary rocks.

Caralampi soils make up about 65 percent of the association, White House soils 20 percent and other soils about 15 percent. The included soils consist mostly of small areas of Oracle and Hathaway on uplands and Comoro and other alluvial soils along narrow drainageways.

The native vegetation is mostly grama grasses, plains lovegrass, Arizona cottontop, bush muhly, sand dropseed, calliandra, catclaw, whitethorn, pricklypear and cholla cacti, and annual grasses and forbs. A few oak and juniper may grow on north-facing slopes at higher elevations.

Under good management the soils have fair to good potential for the production of range forage. Good wildlife habitat is along drainageways.

Factors limiting the potential of these areas for homesite development are high shrink-swell and slow permeability in the White House soils and slope and high gravel content in the Caralampi soils.


[page 102]

TS9 Latene-Nickel-Pinaleno Association

Deep, gravelly, limy, moderately coarse to moderately fine-textured, nearly level to very steep soils on dissected alluvial fan surfaces.

  • Soil Classification
    • Typic Calciorthids
    • Typic Haplargids
  • Percent Slope 1 to 60
  • Elevation 700 to 1,640 m (2,300 to 5,400 ft)
  • Mean Annual Precipitation 250 to 410 mm (10 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 40 to 65
  • Mean January Air Temperature 4 to 10 C (40 to 50 F)
  • Mean July Air Temperature 27 to 29 C (80 to 85 F)
  • Mean Annual Soil Temperature 16 to 22 C (61 to 72 F)
  • Frost-Free Days 180 to 270
  • Area and Percent of State 534,200 ha (1,320,000 ac), 1.8
  • Land Uses rangeland and wildlife habitat; some building sites on Pinaleno, Nickel and Palos Verdes soils near Tucson

This association consists of well-drained soils on deeply dissected old alluvial fans and terraces. The soils formed in old alluvium derived from granite, gneiss, limestone and other sedimentary and igneous rocks.

Latene soils make up about 30 percent of this association, Nickel soils 20 percent, Pinaleno soils 20 percent and numerous minor soils 30 percent. The minor included soils, which may be extensive at some sites, are Tres Hermanos, Palos Verdes, Whitlock, Rillino and Dona Ana. Glendale, Comoro, Anthony and other Torrifluvents are along drainageways.

The native vegetation consists of creosotebush, whitethorn, paloverde, bursage, scattered Mohave yucca and mesquite, saguaro and other cacti, black grama, bush muhly, threeawn and annual grasses and forbs.

This association has low potential for producing livestock forage. The soils have low to fair potential for wildlife habitat.

Factors limiting the potential of these areas for urban development are the excessive slope and high gravel content of the Nickel and Pinaleno soils and high lime content in the lower horizons of all major soils. These limitations have been partially overcome or compensated for in the foothills near Tucson by proper engineering design and construction techniques.


[page 103]

TS10 Chiricahua-Cellar Association 5

Shallow, gravelly, moderately coarse to fine-textured, gently rolling to hilly soils on low granitic foothills.

  • Soil Classification
    • Ustollic Haplargids
    • Lithic Torriorthents
  • Percent Slope 5 to 25
  • Elevation 610 to 1,460 m (2,000 to 4,800 ft)
  • Mean Annual Precipitation 280 to 480 mm (11 to 19 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 60
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 27 to 29 C (80 to 85 F)
  • Mean Annual Soil Temperature 15 to 22 C (60 to 72 F)
  • Frost-Free Days 220 to 260
  • Area and Percent of State 58,070 ha (143,500 ac), 0.2
  • Land Uses rangeland and wildlife habitat; some recreation and homesites

This association consists of well-drained soils formed on low granitic mountains and pediments. The soils formed in the residuum of strongly weathered coarse-grained granite.

Oracle (Chiricahua) soils make up about 50 percent of this association, Romero (Cellar) soils 30 percent and included minor soils and rock outcrop about 20 percent. The included soils are mostly small areas of Caralampi and White House and narrow bodies of Comoro and other Torrifluvents along drainageways.

The dominant native vegetation is cacti and shrubs and grasses including shrub live oak, manzanita, calliandra, turpentinebush, range ratany, bullgrass, grama grasses, plains lovegrass, wolftail, Arizona cottontop, and numerous other grasses and shrubs. Emory oak and juniper grow at higher elevations.

Under good management these soils have good potential for the production of livestock and wildlife forage. Areas of this association receive somewhat higher precipitation than is normal for the Thermic Semiarid associations, 250 to 310 mm (10 to 16 in). These areas receive up to 480 mm (19 in) mean annual precipitation.

Factors limiting the potential of these areas for development of homesites are slope, depth to bedrock and water supply.


[page 104]

TS11 Gothard-Crot-Stewart Association

Shallow to deep, moderately well and somewhat poorly drained, saline-sodic, nearly level soils on playas.

  • Soil Classification
    • Typic Natrargids
    • Aquic Natrustalfs
    • Typic Durorthids
  • Percent Slope mostly less than 1; some short, steep slopes
  • Elevation 1,180 to 1,300 m (3,900 to 4,300 ft)
  • Mean Annual Precipitation 280 mm (11 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 30 to 35
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 24 to 27 C (75 to 80 F)
  • Mean Annual Soil Temperature 17 C (62 F)
  • Frost-Free Days 180 to 220
  • Area and Percent of State 58,280 ha (144,000 ac), 0.2
  • Land Uses rangeland and wildlife habitat; some homesites and, on Gothard soils, irrigated cropland

This association consists of imperfectly drained, saline-sodic soils surrounding the Willcox Playa. The soils formed in old lacustrine sediments derived from igneous and sedimentary rocks.

Gothard soils make up about 35 percent of the association, Crot soils 25 percent, Stewart soils 25 percent and several minor soils and the Willcox Playa about 15 percent. The minor soils include areas of Duncan, Dry Lake, Karro, Elfrida, Cogswell, Guest and Comoro.

The native vegetation is alkali sacaton, saltgrass, tobosa, scattered mesquite and annual grasses. Many small barren playas are common.

This association has limited potential for the production of livestock forage. Cattle graze these coarse grasses when they are green and tender, but the grasses have low palatability when dry and mature. Excess salt and alkali severely limit these soils for crop production.

The major limiting factors for most community uses are excess salt and alkali, very slow permeability, poor drainage, high water table in Crot soils and depth to pan in Stewart soils.


[page 105]

TS12 Continental-Latene-Pinaleno-Association

Deep, gravelly, medium to fine-textured, nearly level to steep soils on dissected alluvial fan surfaces.

  • Soil Classification
    • Typic Haplargids
    • Typic Calciorthids
  • Percent Slope mostly 1 to 35; to 60 on some short escarpments
  • Elevation 640 to 1,400 m (2,100 to 4,600 ft)
  • Mean Annual Precipitation 250 to 360 mm (10 to 14 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 35 to 60
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 17 to 22 C (62 to 72 F)
  • Frost-Free Days 205 to 275
  • Area and Percent of State 458,530 ha (1,133,000 ac), 1.6
  • Land Uses rangeland and wildlife habitat; some homesites and, around Roosevelt Lake, recreation

This association consists of well-drained soils on dissected old terraces and alluvial fans.

Continental soils make up about 30 percent of the association, Latene soils 25 percent, Pinaleno soils 25 percent and several minor soils 20 percent. The minor soils are mostly small areas of Nickel, Eba, Tres Hermanos, Cave, Mohave, Dona Ana and Whitlock and narrow bands of Anthony, Gila and other Torrifluvents along drainageways.

The dominant native vegetation is mesquite, whitethorn, catclaw, cholla and pricklypear cacti, wolfberry, creosotebush, burroweed, grama grasses, bush muhly, tobosa, threeawn and annuals.

The potential for the production of livestock and wildlife forage is only fair due to low precipitation and the predominance of brushy plant species. Good wildlife habitat is along drainageways.

Factors limiting the potential of these areas for the development of homesites and recreation are slow permeability and high shrink-swell in Continental soils, slope and high gravel content in Pinaleno soils and high lime content in the substrata of Latene soils.


[page 106]

TS13 Karro-Gothard Association

Deep, well and moderately well-drained, medium and moderately fine-textured, nearly level soils on lower valley slopes and playas.

  • Soil Classification
    • Ustollic Calciorthids
    • Typic Natrargids
  • Percent Slope mostly none to 2; some to 15
  • Elevation 1,030 to 1,400 m (3,400 to 4,600 ft)
  • Mean Annual Precipitation 250 to 300 mm (10 to 12 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 30 to 45
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 24 to 27 C (75 to 80 F)
  • Mean Annual Soil Temperature 16 to 19 C (60 to 66 F)
  • Frost-Free Days 170 to 230
  • Area and Percent of State 71,230 ha (176,000 ac), 0.2
  • Land Uses rangeland, wildlife habitat and irrigated cropland

This association consists of calcareous and sodic soils. The soils formed in old lacustrine sediments derived from igneous and sedimentary rocks.

Karro and Hondale 6 soils make up about 40 percent of the association, Gothard soils 35 percent and several minor soils about 25 percent. These minor soils consist of scattered areas of Elfrida, McAllister, Pima and Grabe in the Sulphur Springs Valley in Cochise County and areas of Hantz, Dona Ana, Glendale and Artesia in the San Simon Valley in Cochise and Graham counties.

The dominant native vegetation is alkali sacaton, tobosa, fluffgrass, burroweed, creosotebush, fourwing saltbush, blackbrush, mesquite and annuals.

The association has low potential for producing livestock forage. It has fair potential for growing irrigated crops where the sodium content is low or can be leached by adding amendments. The principal crops grown under irrigation are alfalfa, cotton and small grains. The high lime content may cause chlorosis in small grains. The potential for the improvement of wildlife habitat is good where the soils are irrigated and poor where nonirrigated.

Factors limiting the potential of these soils for development of homesites are the moderately slow permeability of the Karro soils and the very slow permeability of the Gothard soils, which are poor for use as septic tank absorption fields. Also, the Karro soils are high in lime content and the Gothard soils are saline-sodic.


[page 107]

TS14 Nickel-Latene-Cave Association

Deep and shallow, limy and gravelly, medium and moderately coarse-textured, nearly level to very steep soils on dissected alluvial fan surfaces.

  • Soil Classification
    • Typic Calciorthids
    • Typic Paleorthids
  • Percent Slope mostly 5 to 30; range is none to 60
  • Elevation 730 to 1,520 m (2,400 to 5,000 ft)
  • Mean Annual Precipitation 250 to 360 m (10 to 14 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 35 to 50
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 18 to 22 C (64 to 72 F)
  • Frost-Free Days 180 to 265
  • Area and Percent of State 414,820 ha (1,025,000 ac), 1.4
  • Land Uses rangeland and wildlife habitat; most of Tucson is in this association

This association consists of well-drained soils on dissected old alluvial fans and terrace escarpments that are mostly along the San Pedro River and the San Simon Creek in Cochise County and in the Tucson Basin. The soils formed in calcareous old alluvium derived from igneous and sedimentary rocks.

Nickel soils make up about 25 percent of the association, Latene soils 25 percent, Cave soils 15 percent, Rillino soils 20 percent and minor soils 15 percent. These minor soils, which may be extensive in some areas, include Tres Hermanos, Pinaleno, Dona Ana, Continental, Kimbrough, Hathaway and Forrest. Narrow bands of Pima, Guest, Stellar and Grabe soils are in and along drainageways.

The dominant native vegetation is creosotebush, whitethorn, cacti, paloverde (Tucson area), range ratany, scattered Mohave yucca and mesquite, fluffgrass, black grama and annual grasses and forbs.

The soils have limitations for development of homesites and commercial sites due to the high lime content of all soils, shallow depth to hardpan in Cave soils, high gravel content in Nickel and Rillino soils and excessive slope in Nickel and some Rillino soils. In the metropolitan Tucson area these limitations have been partially overcome or compensated for by proper engineering design and construction techniques.


[page 108]

TS15 Bonita-Graham-Rimrock Association

Shallow to deep, fine-textured, nearly level to steep soils on plains, hills and mountains.

  • Soil Classification
    • Typic Chromusterts
    • Typic Argiustolls
  • Percent Slope none to 15 on basalt and ash-flow tuffs; 50 or more on large cinder cones and andesitic mountains
  • Elevation 1,030 to 1,670 m (3,400 to 5,500 ft)
  • Mean Annual Precipitation mostly 300 to 410 mm (12 to 16 in); up to 500 mm (20 in) in some areas
  • Winter Precipitation as the Percentage of Annual Precipitation 30 to 65
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 15 to 20 C (59 to 68 F)
  • Frost-Free Days 160 to 220
  • Area and Percent of State 330,440 ha (816,500 ac), 1.1
  • Land Uses rangeland and wildlife habitat; some building sites

This association consists of well-drained soils formed in residuum and alluvium weathered from basalt, andesite, ash-flow tuffs, cinders and related volcanic rocks.

Bonita soils make up about 30 percent of the association, Graham soils 20 percent, Rimrock soils 20 percent and minor associated soils 30 percent. These minor soils may be quite extensive in some areas and are mostly Bernardino, White House, Sontag, Krentz, Guest and Pima and small areas of rock outcrop.

The native vegetation is mostly grass. Grasses include tobosa, vine-mesquite, curlymesquite, plains bristlegrass, grama grasses and cane bluestem. Scattered mesquite, catclaw, agave, pricklypear and annual grasses and forbs also occur. Ocotillo is present on Graham soils and oak and juniper occur at higher elevations.

This association has low to fair potential for livestock grazing. Livestock avoid areas with cobbly, stony surfaces and areas that have wide cracks. In addition, the dominant tobosa has low palatability when dry and mature. Wildlife use on these soils is mostly transient due to lack of cover.

Factors limiting the potential of these areas for building sites are high shrink-swell, depth to bedrock on Graham and Rimrock soils and slope on Graham soils.


[page 109]

TS16 Penthouse-Latene-Cornville Association

Deep, medium to fine-textured, nearly level to moderately steep soils on dissected fan surfaces and valley slopes.

  • Soil Classification
    • Ustollic Haplargids
    • Typic Calciorthids
    • Typic Haplargids
  • Percent Slope mostly 1 to 10; 30 or more on some escarpments
  • Elevation 910 to 1,400 m (3,000 to 4,600 ft)
  • Mean Annual Precipitation 280 to 410 mm (11 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 55
  • Mean January Air Temperature 2 to 4 C (35 to 40 F)
  • Mean July Air Temperature 24 to 27 C (75 to 80 F)
  • Mean Annual Soil Temperature 15 to 19 C (59 to 66 F)
  • Frost-Free Days 180 to 235
  • Area and Percent of State 31,160 ha (77,000 ac), 0.1
  • Land Uses rangeland and wildlife habitat; some homesites and irrigated cropland and pasture on Cornville soils

This association consists of well-drained soils on dissected fan surfaces along the Verde River and its tributaries. They formed in old alluvial and lacustrine sediments derived from calcareous sedimentary and volcanic rocks.

Penthouse soils make up about 30 percent of the association, Latene soils 30 percent, Cornville 25 percent and minor included soils about 15 percent. These minor soils are mostly small areas of Continental, Nickel and Rillino and narrow bands of Torrifluvents along drainageways.

The native vegetation is mostly mesquite, snakeweed, creosotebush, fourwing saltbush, cacti, tobosa, grama grasses, wolftail and annual grasses and forbs. A few juniper grow at higher elevations.

These soils have fair to good potential for forage production but are limited by low precipitation. They commonly are used as winter range for cattle and sheep due to their proximity to the high plateaus to the east. Crops grown on Cornville and possibly Latene soils are alfalfa, corn, small grains and pasture grasses.

The dominant limiting factors for community uses on these soils are the cobbly surface and clayey, slow permeability of subsoils of Penthouse soils and the high lime content in the substratum of all major soils.


[page 110]

TS17 Signal-Grabe Association

Deep, medium and fine-textured, nearly level to gently sloping soils on high valley plains.

  • Soil Classification
    • Aridic Paleustolls
    • Typic Torrifluvents
  • Percent Slope none to 5
  • Elevation 1,460 to 1,670 m (4,800 to 5,500 ft)
  • Mean Annual Precipitation 350 to 430 mm (14 to 17 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 55
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 15 to 19 C (60 to 66 F)
  • Frost-Free Days 160 to 210
  • Area and Percent of State 43,910 ha (108,500 ac), 0.1
  • Land Uses rangeland and wildlife habitat

This association consists of well-drained soils on gently sloping uplands, broad floodplains and low fans. The soils formed in alluvium derived mostly from volcanic rocks, but also minor sedimentary rocks.

Signal soils make up about 50 percent of the association, Grabe soils 30 percent and the other included soils about 20 percent. The included soils are mostly areas of Bonita, Rimrock and Graham on the uplands and Pima and Guest in floodplains.

The dominant vegetation is grama grasses, tobosa, curlymesquite, calliandra, catclaw and cacti on the Signal soils and mesquite, gramas, threeawn and bush muhly on the Grabe soils. Under good range management they have fair to good potential for the production of livestock forage.

One factor limiting the potential of these soils for homesite development is the slow permeability of the Signal soils, which are poor for use as septic tank absorption fields. Also, the Signal soils have high shrink-swell potential and the Grabe soils are subject to flooding.


[page 111]

TS18 Graham-Lampshire-House Mountain Association

Shallow, gravelly and cobbly, medium to fine-textured, rolling to very steep soils on hills and mountains.

  • Soil Classification
    • Lithic Argiustolls
    • Lithic Haplustolls
    • Lithic Torriorthents
  • Percent Slope 5 to 60
  • Elevation 1,060 to 1,670 m (3,500 to 5,500 ft)
  • Mean Annual Precipitation 300 to 410 mm (12 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 40 to 60
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 24 to 29 C (75 to 85 F)
  • Mean Annual Soil Temperature 15 to 20 C (59 to 68 F)
  • Frost-Free Days 160 to 220
  • Area and Percent of State 242,420 ha (599,000 ac), 0.8
  • Land Uses rangeland and wildlife habitat

This association consists of shallow and very shallow, well-drained soils and rock outcrop on volcanic hills and mountains. The soils formed in residuum weathered from basalt, ash-tuff, andesite, dacite and other related volcanic rocks.

Graham soils make up about 40 percent of the association, Lampshire soils 30 percent, House Mountain soils 15 percent and rock outcrop and included closely associated soils about 15 percent. The included soils are mostly small areas of Limpia, Rimrock, Bonita, Guest and Pima.

The native vegetation includes mesquite, catclaw, calliandra, ocotillo, shrub live oak, tobosa, grama grasses, curlymesquite, plains lovegrass, cane bluestem, agave, sotol, cacti and forbs.

These soils have fair to good potential to produce livestock and wildlife forage; however, the cobbly, stony surface and steep slopes preclude heavy use by livestock.

Factors limiting the potential for homesite development on these soils are shallow depth to rock, high content of gravels, cobbles or stones and steep slopes.


[page 112]

TS19 Anthony-Sonoita Association

Deep, moderately coarse-textured, nearly level to gently sloping soils on alluvial fans.

  • Soil Classification
    • Typic Torrifluvents
    • Typic Haplargids
  • Percent Slope none to 5
  • Elevation 670 to 1,150 m (2,200 to 3,800 ft)
  • Mean Annual Precipitation 250 to 350 mm (10 to 14 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 35 to 50
  • Mean January Air Temperature 7 to 10 C (45 to 50 F)
  • Mean July Air Temperature 29 to 32 C (85 to 90 F)
  • Mean Annual Soil Temperature 20 to 22 C (68 to 72 F)
  • Frost-Free Days 250 to 270
  • Area and Percent of State 84,180 ha (208,000 ac), 0.3
  • Land Uses rangeland, wildlife habitat, recreation and urban

This association consists of well-drained soils on alluvial fans at the base of granitic mountains near Tucson. They formed in mixed alluvium weathered from granite, gneiss and some volcanic rocks.

Anthony soils make up about 35 percent of the association, Sonoita soils 30 percent and minor included soils about 35 percent. These minor soils, which may be extensive in some places, are mostly small areas of Bucklebar, Valencia, Palos Verdes, Pinaleno, Tres Hermanos and Tubac. Narrow areas of sandy Torrifluvents are along drainageways.

The native vegetation consists of paloverde, mesquite, whitethorn, bursage, some ironwood, cholla, saguaro and pricklypear cacti, snakeweed, bush muhly, threeawn and annual grasses and forbs.

Under good management these soils have fair to good potential for the production of livestock and wildlife forage. Many areas are in poor condition from overgrazing due to their easy accessibility.

The association has good potential for homesites and other community development if protected from flooding.


[page 113]

7.2.4. Mesic Arid Soils

FIGURE 48. Representative Mesic Arid Soils Soilscape and Profiles (D. M. Hendricks)


[page 114]

FIGURE 49. Geographic Distribution of Mesic Arid (MA) Soils in Arizona (D. M. Hendricks)

MA1 Badland-Torriorthents-Torrifluvents Association
MA2 Moenkopie-Shalet-Tours Association
MA3 Sheppard-Fruitland-Rock Outcrop Association
MA4 Tours-Navajo Association
MA5 Torriorthents-Torrifluvents Association
MA6 Fruitland-Camborthids-Torrifluvents Association

MA Mesic Arid Soils

Mesic Arid Soils have a mean annual soil temperature of 8 C (47 F) or more, but less than 15 C (59 F). The difference between mean summer and mean winter temperatures is greater than 5 C (9 F) measured at a depth of 50 cm (20 in) or at the soil-bedrock interface in shallow soils. These soils receive 150 to 250 mm (6 to 10 in) mean annual precipitation. Mesic Arid Soils are extensive on the Colorado Plateau. The elevation of Mesic Arid Soils is intermediate. They cover about 3,546,990 ha (8,764,500 ac) or 12 percent of Arizona.


[page 115]

MA1 Badland-Torriorthents-Torrifluvents Association

Shallow and deep, moderately fine and fine-textured, moderately sloping to very steep soils on eroded uplands and nearly level floodplains.

  • Soil Classification
    • Typic Torriorthents
    • Typic Torrifluvents
  • Percent SlopeBadland, none to 60 or more; Torriorthents-Torrifluvents, none to 8
  • Elevation 1,400 to 1,820 m (4,600 to 6,000 ft)
  • Mean Annual Precipitation 150 to 300 mm (6 to 12 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 60
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature 11 to 15 C (51 to 59 F)
  • Frost-Free Days 130 to 180
  • Area and Percent of State 489,280 ha (1,209,000 ac), 1.7
  • Land Uses rangeland, wildlife habitat and recreation

This association consists of Badland and shallow, well-drained soils formed on shale and sandstone and deep, well-drained soils formed in recent alluvium derived from sedimentary rocks.

Badland makes up about 40 percent of the association, Torriorthents 25 percent, Torrifluvents 25 percent and minor areas of associated soils and rock outcrop, about 10 percent.

Claysprings is the dominant Torriorthent and Tours and Navajo are the major Torrifluvents in the association. The minor soils are small areas of Jocity, Sheppard, Clovis, Shalet, Moenkopie and Fruitland.

The native vegetation is very sparse and consists mostly of fourwing saltbush, shadscale, Mormon-tea, alkali sacaton, galleta, blue grama, Indian ricegrass and annuals.

The Badland and Torriorthents have low potential for forage production. The Torrifluvents that are not entrenched or eroded have fair to good potential under good management to produce forage. The major limitation is low rainfall. Small areas of the Tours and Navajo soils are used as irrigated cropland.

Limitations of the potential for construction of structures on these soils are shallow depths, steep slopes in the badlands, high shrink-swell and slow permeability of the Torriorthents. The Torrifluvents may be subject to flooding and generally have low strength.

Areas of the Badlands are unique scenic attractions. They include the Painted Desert, Monument Valley and the Petrified Forest National Monument.


[page 116]

MA2 Moenkopie-Shalet-Tours Association

Shallow and deep, moderately coarse to moderately fine-textured, nearly level to rolling soils on sandstone and shale plateaus.

  • Soil Classification
    • Lithic Torriorthents
    • Typic Torriorthents
    • Typic Torrifluvents
  • Percent Slope mostly 1 to 5; range is none to 20
  • Elevation 1,340 to 1,970 m (4,400 to 6,500 ft)
  • Mean Annual Precipitation 150 to 250 mm (6 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 65
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 9 to 15 C (49 to 59 F)
  • Frost-Free Days 130 to 185
  • Area and Percent of State 563,750 ha (1,393,000 ac), 1.9
  • Land Uses rangeland and wildlife habitat

This association consists of well-drained soils on plateaus and floodplains. The soils formed in residuum and alluvium weathered from sandstone, shale and conglomerate rocks.

Moenkopie soils make up about 60 percent of the association, Shalet soils 15 percent, Tours soils 15 percent, and minor areas of associated soils, 10 percent. The minor soils are mostly small areas of Ives, Jocity, Trail, Clovis, Palma, Claysprings and Purgatory series. Also included are small areas of sandstone rock outcrop.

The dominant native vegetation includes alkali sacaton, galleta, fourwing saltbush, blue and black grama, sand dropseed and Mormon-tea, and some sagebrush and scattered juniper.

Moenkopie and Shalet soils have low potential for forage production. Tours soils that receive extra water from runoff have fair to good potential under good management to produce forage.

Factors limiting the potential of these soils for homesite development are the shallow depths to rock in the Moenkopie and Shalet soils. Also, the Tours soils may be subject to flooding and have moderately slow permeability, which is poor for use as septic tank absorption fields.


[page 117]

MA3 Sheppard-Fruitland-Rock Outcrop Association

Deep, coarse and moderately coarse-textured, nearly level to rolling soils and rock outcrop on plains.

  • Soil Classification
    • Typic Torripsamments
    • Typic Torriorthents
  • Percent Slope 2 to 15; some to 30
  • Elevation 1,520 to 2,120 m (5,000 to 7,000 ft)
  • Mean Annual Precipitation 150 to 250 mm (6 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 65
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 10 to 14 C (50 to 58 F)
  • Frost-Free Days 130 to 170
  • Area and Percent of State 865,250 ha (2,138,000 ac), 2.9
  • Land Uses rangeland, wildlife habitat and recreation

This association consists of somewhat excessively drained and well-drained soils and rock outcrop on plains and plateaus. The plains are broken by prominent mesas, buttes and escarpments. Steep, rock-walled canyons form the sides of the drainages that traverse the areas. The soils formed in aeolian sandy material weathered from sandstone and shale.

Sheppard soils make up about 35 percent of the association, Fruitland soils 35 percent, rock outcrop about 15 percent and minor areas of associated soils and dune land and Badland about 15 percent. The minor soils are mostly small areas of Moenkopie, Shalet and Palma. The dune land occurs as scattered areas of low, poorly stabilized dunes 0.3 to 3 m (1 to 10 ft) high. The Badland consists of small areas of eroded shaly materials.

The native vegetation is dominantly sand sagebrush and sparse areas of Mormon-tea, blackbrush, rabbitbrush, Indian ricegrass, sand dropseed, galleta, grama grasses, threeawn, Russian thistle and other annual weeds and grasses. A few scattered stands of juniper and pinyon pine grow in rocky areas. The potential for livestock and wildlife forage production is low due to low precipitation and low water-holding capacity of the major soils.

Limitations for potential homesite development on these soils are few. The sandy texture of the Sheppard soils, however, is a severe limitation to shallow excavations.

Some areas, such as Monument Valley and Nakai and Piute canyons, are noted scenic attractions because of their vivid colors and unique rock formations. The Betatakin and Keet Seel Ruins and other cliff dwellings in the Navajo National Monument are in this mapping unit. However, until more facilities are built, much of the area can be reached only with great difficulty.


[page 118]

MA4 Tours-Navajo Association

Deep, moderately fine and fine-textured, nearly level to gently sloping soils on floodplains.

  • Soil Classification Typic Torrifluvents
  • Percent Slope none to 3
  • Elevation 1,400 to 1,730 m (4,600 to 5,700 ft)
  • Mean Annual Precipitation 150 to 250 mm (6 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 60
  • Mean January Air Temperature -1 C (30 F)
  • Mean July Air Temperature 21 to 24 C (70 to 75 F)
  • Mean Annual Soil Temperature 10 to 15 C (50 to 59 F)
  • Frost-Free Days 155 to 175
  • Area and Percent of State 224,000 ha (553,500 ac), 0.8
  • Land Uses rangeland, wildlife habitat and irrigated cropland; some homesites and community uses

This association consists of well-drained soils on the floodplains and adjacent low alluvial fans of the Little Colorado River and its major tributaries. The soils formed in recent alluvium derived from sedimentary and volcanic rocks.

Tours soils make up about 35 percent of the association, Navajo soils 35 percent and minor areas of associated soils and riverwash about 30 percent. The minor soils are mostly Ives, Trail and Jocity.

The native vegetation is mostly fourwing saltbush, shadscale, rabbitbrush, sand sagebrush, galleta, alkali sacaton, blue and black grama, threeawn, saltgrass and annuals. Tamarisk, desertwillow and cottonwood trees grow along the streams in some areas.

The soils have fair potential under good management for producing livestock forage. Limited precipitation is the major factor, but these soils receive runoff from adjacent areas during wet periods. Riparian vegetation and adjacent irrigated cropland provide elements for good wildlife habitat in this association. The short growing season limits crops grown in irrigated areas to alfalfa, corn, small grain and pasture grasses. Saline areas require careful management and reclamation practices.

Factors limiting the potential of these areas for homesites and community uses are flooding hazard, moderately slow to very slow permeability, low bearing strength, salinity, erosion hazard and potential frost action.


[page 119]

MA5 Torriorthents-Torrifluvents Association

Shallow and deep, moderately fine and fine-textured, nearly level to gently sloping soils on valley slopes and floodplains.

  • Soil Classification
    • Typic Torriorthents
    • Typic Torrifluvents
  • Percent Slope none to 5
  • Elevation 1,520 to 1,760 m (5,000 to 5,800 ft)
  • Mean Annual Precipitation 200 to 250 mm (8 to 10 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 60
  • Mean January Air Temperature -1 C (30 F)
  • Mean July Air Temperature 21 to 24 C (70 to 75 F)
  • Mean Annual Soil Temperature 11 to 13 C (52 to 56 F)
  • Frost-Free Days 130 to 170
  • Area and Percent of State 38,450 ha (95,000 ac), 0.1
  • Land Uses rangeland and wildlife habitat; some irrigated cropland and pasture, and some villages

This association consists of well-drained soils on the floodplains and adjacent fans and low uplands along Chinle Wash and Lukachukai Creek in the Navajo Indian Reservation. The soils formed in residuum and alluvium derived from clay, shale, sandstone and conglomerate.

The Torriorthents and small areas of Badland make up about 70 percent of the association and Torrifluvents 30 percent.

The shallow Claysprings and Shalet soils are the dominant Torriorthents. The deep Tours and Navajo soils are the major Torrifluvents. Included with the Torrifluvents are small areas of Ives, Jocity and Trail, and riverwash.

The native vegetation is mostly alkali sacaton, saltgrass, galleta, blue and black grama, threeawn, fourwing saltbush, sagebrush, rabbitbrush and annual weeds and grasses. Tamarisk, desertwillow and cottonwood trees grow along streams in some areas.

The soils have fair potential under good management for producing livestock forage. Limited precipitation is the major factor, but these soils receive runoff from adjacent areas during wet periods. Riparian vegetation along the streams and adjacent irrigated cropland provide good wildlife habitat. The short growing season limits crops grown in irrigated areas to alfalfa, corn and pasture grasses. Saline areas require careful management and reclamation practices.

Factors limiting the potential of these areas for homesites and community uses are flooding hazard, moderately slow to very slow permeability, low bearing strength, salinity, erosion hazard and potential frost action.


[page 120]

MA6 Fruitland-Camborthids-Torrifluvents Association

Shallow to deep, moderately coarse to moderately fine-textured, nearly level to hilly soils on upland plains.

  • Soil Classification
    • Typic Torriorthents
    • Camborthids
    • Typic Torrifluvents
  • Percent Slope 2 to 20
  • Elevation 1,520 to 2,060 m (5,000 to 6,800 ft)
  • Mean Annual Precipitation 150 to 300 mm (6 to 12 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 60
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature 10 to 14 C (50 to 58 F)
  • Frost-Free Days 130 to 170
  • Area and Percent of State 1,366,270 ha (3,376,000 ac), 4.6
  • Land Uses rangeland and wildlife habitat; some cropland

This association consists of well-drained soils on the high plains. The plains are broken by occasional steep-sided drainageways and scattered buttes. The soils formed in a thick to thin, wind- and water-laid mantle of alluvium weathered from sandstone and shale.

Fruitland soils and closely associated unnamed shallow and moderately deep Torriorthents make up about 50 percent of the association, Camborthids 30 percent, Torrifluvents 15 percent and small areas of rock outcrop and minor included soils 5 percent. The Torrifluvents are mostly Ives and Tours series.

The dominant native vegetation is sand sagebrush, galleta, blue and black grama, Indian ricegrass, sand dropseed, threeawn and rabbitbrush. Juniper and a few pinyon pine grow at higher elevations.

This association has low to fair potential under good management for livestock forage production. Limited precipitation is the major factor. The best potential is in those areas that receive runoff from adjacent areas. Crops grown are mostly small patches of corn, alfalfa and pasture grasses.

The Fruitland soils and Camborthids have good potential for homesites and community uses. The Torrifluvents are subject to seasonal flooding.


[page 121]

7.2.5. Mesic Semiarid Soils

FIGURE 50. Representative Mesic Semiarid Soils Soilscape and Profiles (D. M. Hendricks)


[page 122]

FIGURE 51. Geographic Distribution of Mesic Semiarid (MS) Soils in Arizona (D. M. Hendricks)

MS1 Tortugas-Purner-Jacks Association
MS2 Winona-Boysag-Rock Outcrop Association
MS3 Palma-Clovis-Trail Association
MS4 Rudd-Bandera-Cabezon Association
MS5 Roundtop-Boysag-Association
MS6 Lithic Torriorthents-Lithic Haplargids-Rock Outcrop Association
MS7 Cabezon-Thunderbird-Springerville Association
MS8 Pastura-Poley-Partri Association
MS9 Lonti-Balon-Lynx Association
MS10 Pastura-Abra-Lynx Association

MS Mesic Semiarid Soils

Mesic Semiarid Soils have a mean annual soil temperature of 8 C (47 F) or more, but less than 15 C (59 F). The difference between mean summer and mean winter temperatures is greater than 5 C (9 F) measured at a depth of 50 cm (20 in) or at the soil-bedrock interface in shallow soils. The mean annual precipitation on these soils ranges from 250 to 460 mm (10 to 18 in). Their elevation is intermediate. Mesic Semiarid Soils cover about 5,328,080 ha (13,165,500 ac), or 18 percent of Arizona.


[page 123]

MS1 Tortugas-Purner-Jacks Association

Shallow to moderately deep, gravelly and cobbly, medium to fine-textured, undulating to steep soils on hills and mountains.

  • Soil Classification
    • Lithic Haplustolls
    • Udic Haplustalfs
  • Percent Slope 2 to 45
  • Elevation 1,370 to 2,060 m (4,500 to 6,800 ft)
  • Mean Annual Precipitation mostly 300 to 410 mm (12 to 16 in); to 460 mm (18 in) in a few areas
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 70
  • Mean January Air Temperature -1 to 7 C (30 to 45 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature 9 to 15 C (48 to 59 F)
  • Frost-Free Days 140 to 160
  • Area and Percent of State 180,500 ha (446,000 ac), 0.6
  • Land Uses rangeland, wildlife habitat and recreation; a few rock quarries

This association consists of well-drained soils formed in residuum on limestone and sandstone ridges, hills and mountains south of the Grand Canyon.

Tortugas soils make up about 45 percent of the association, Purner soils 20 percent, Jacks soils 20 percent and other associated soils and rock outcrop 15 percent. The included soils are mostly small areas of Boysag, Dye, Thunderbird, Springerville, Pastura, Moenkopie and Lynx. These included soils may be fairly extensive in some areas.

The dominant native vegetation is pinyon pine, juniper, ceanothus, cliffrose, shrub live oak, mountainmahogany, wolftail, spike muhly and blue, black and sideoats grama. Scattered ponderosa pine grow on Jacks soils in some areas.

The potential for livestock forage production is fair to good. Areas that have steep slopes and areas that lack water facilities limit use by domestic livestock. The potential for use as woodland and rangeland wildlife habitat is good.

The major factors limiting the potential of these soils for building sites are depth to bedrock, slope and low bearing strength, and high shrink-swell of the Jacks soils.


[page 124]

MS2 Winona-Boysag-Rock Outcrop Association

Shallow, medium and fine-textured, undulating to rolling soils and rock outcrop on plateaus and plains.

  • Soil Classification
    • Lithic Torriorthents
    • Lithic Ustollic Haplargids
  • Percent Slope mostly 2 to 15; 50 or more on breaks and escarpments
  • Elevation 1,400 to 2,000 m (4,600 to 6,600 ft)
  • Mean Annual Precipitation mostly 250 to 410 mm (10 to 16 in); to 500 mm (20 in) in a few higher places
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 70
  • Mean January Air Temperature -1 to 7 C (30 to 45 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature 10 to 14 C (50 to 58 F)
  • Frost-Free Days 130 to 180
  • Area and Percent of State 998,390 ha (2,467,000 ac), 3.4
  • Land Uses rangeland, wildlife habitat and recreation

This association consists of shallow, well-drained soils and rock outcrop on broad limestone and sandstone plateaus and plains. The soils formed in residuum on limestone and calcareous sandstone.

Winona soils make up about 60 percent of the association, Boysag soils 15 percent, limestone and sandstone rock outcrop 15 percent and included associated soils 10 percent. These included soils consist mostly of small areas of Tortugas, Welring, Moenkopie, Poley and Tusayan on uplands, and Tours and Lynx along drainageways.

The dominant native vegetation is juniper, pinyon pine, cliffrose, ceanothus, big sagebrush, blue and black grama, Indian ricegrass, pine dropseed, spike muhly and galleta.

This association has good potential to produce livestock forage but many areas have reduced gross yields due to juniper and pinyon encroachment. The potential use for rangeland wildlife habitat is fair. The best habitat is in the higher wooded areas.

Walnut Canyon and part of the Wupatki National Monument and Meteor Crater are within this association. The association borders the Grand Canyon in places and part lies within the Grand Canyon National Park.

Factors limiting the potential of these areas for building sites, sanitary facilities and recreational areas are shallow depth to bedrock, rock fragments on the surface and excessive slope on the steeper areas.


[page 125]

MS3 Palma-Clovis-Trail Association

Deep, coarse to moderately fine-textured, nearly level to rolling soils on plains.

  • Soil Classification
    • Ustollic Haplargids
    • Typic Torrifluvents
  • Percent Slope 1 to 15
  • Elevation 1,460 to 2,120 m (4,800 to 7,000 ft)
  • Mean Annual Precipitation mostly 250 to 360 mm (10 to 14 in); range is 230 to 410 mm (9 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 65
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 21 to 24 C (70 to 75 F)
  • Mean Annual Soil Temperature 9 to 14 C (48 to 57 F)
  • Frost-Free Days 125 to 175
  • Area and Percent of State 1,743,040 ha (4,307,000 ac), 5.9
  • Land Uses rangeland and wildlife habitat; some cropland

This association consists of extensive areas of well-drained soils on the high plains. The soils formed in alluvium derived from sandstone, limestone and shale rocks.

Palma soils make up about 35 percent of the association, Clovis soils 30 percent, Trail soils 20 percent and included associated soils 15 percent. The included soils are mostly small areas of Moenkopie, Sheppard, Hubert and Millet on uplands, and narrow areas of Tours, Ives and Jocity along drainageways.

The dominant native vegetation is black and blue grama, Indian ricegrass, needleandthread, galleta, winterfat, rabbitbrush, sagebrush in some areas, and widely scattered juniper and pinyon pine in high-precipitation areas.

This association has fair potential under good management for the production of livestock forage but is somewhat limited by low amounts of precipitation. The potential for wildlife habitat is fair. Crops grown under irrigation near St. John are grain sorghum, alfalfa and corn.

Factors limiting the potential of these areas for home and recreation sites are flooding on Trail soils, moderate to low available water capacity on all soils and loose sandy surface soils subject to wind erosion.


[page 126]

MS4 Rudd-Bandera*-Cabezon Association 7

Shallow, gravelly, cobbly and stony, medium and fine-textured, undulating soils on plains and mesa tops and gently rolling to steep soils on cinder cones.

  • Soil Classification
    • Lithic Calciustolls
    • Torriorthentic Haplustolls
    • Lithic Argiustolls
  • Percent Slope 2 to 45
  • Elevation 1,520 to 2,250 m (5,000 to 7,400 ft)
  • Mean Annual Precipitation mostly 250 to 410 mm (10 to 16 in); to 500 mm (20 in) in a few areas
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 70
  • Mean January Air Temperature -1 to 7 C (30 to 45 F)
  • Mean July Air Temperature 16 to 27 C (60 to 80 F)
  • Mean Annual Soil Temperature 8 to 15 C (47 to 59 F)
  • Frost-Free Days 120 to 170
  • Area and Percent of State 495,760 ha (1,225,000 ac), 1.7
  • Land Uses rangeland, wildlife habitat and recreation

This association consists of well-drained and somewhat excessively drained soils formed in residuum and alluvium weathered from basalt, andesite, ash-flow tuffs, cinders and related volcanic rock. They occur on plains, mesa tops and cinder cones.

Rudd soils make up about 40 percent of the association, Bandera-like soils 25 percent, Cabezon soils 20 percent and included associated soils, rock outcrop and cinder land 15 percent. The included soils are mostly small areas of Thunderbird, Springerville, Ziegler, Cross, Pastura and Apache.

The dominant native vegetation is blue, black and sideoats grama, galleta, western wheatgrass, juniper, shrub live oak, big sagebrush, cliffrose, some Mormon-tea, and some pinyon and ponderosa pine at higher elevations.

The association has fair potential for livestock and wildlife forage production. Excessively stony areas limit use by cattle and horses.

Factors that limit the potential of these areas for homesites and recreation are shallow depth to bedrock, high shrink-swell and stones on Cabezon soils; and slope on Bandera-like soils.


[page 127]

MS5 Roundtop-Boysag Association

Shallow and moderately deep, gravelly, fine-textured, undulating to moderately steep soils on plains and mountains.

  • Soil Classification
    • Aridic Argiustolls
    • Lithic Ustollic Haplargids
  • Percent Slope 2 to 30
  • Elevation 1,880 to 2,180 m (6,200 to 7,200 ft)
  • Mean Annual Precipitation 300 to 460 mm (12 to 18 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 60
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 18 to 24 C (65 to 75 F)
  • Mean Annual Soil Temperature 8 to 12 C (47 to 54 F)
  • Frost-Free Days 130 to 160
  • Area and Percent of State 157,020 ha (388,000 ac), 0.5
  • Land Uses rangeland, wildlife habitat and recreation; Grand Canyon National Monument is in part of this unit

This association consists of well-drained soils formed in residuum weathered from limestone and calcareous sandstone on plains and hills. They occur in Coconino County south of the Grand Canyon, an area just southeast of Flagstaff and a small area near Seligman.

Roundtop soils make up about 60 percent of the association, Boysag soils 25 percent and minor areas of associated soils and rock outcrop 15 percent. The minor soils are mostly small areas of Jacks, Winona and Rond on uplands and narrow areas of Lynx and other Torrifluvents along drainageways.

The dominant native vegetation is pinyon and some ponderosa pine, juniper, Gambel oak, mountainmahogany, cliffrose, beargrass, ring muhly, squirreltail, pine dropseed, Indian ricegrass, rabbitbrush, big sagebrush and blue, black and sideoats grama.

These soils have fair to good potential for livestock and wildlife forage production. Pinyon and juniper have invaded some areas and limited growth of better forage species.

The principal factors limiting the potential of these soils for homesites, community uses and recreation are depth to bedrock, slow permeability, high shrink-swell and low bearing strength. Some areas have excessive slope.


[page 128]

MS6 Lithic Torriorthents-Lithic Halpargids-Rock Outcrop Association

Shallow, gravelly and cobbly, moderately coarse to fine-textured, moderately sloping to very steep soils and rock outcrop on hills and mountains.

  • Soil Classification
    • Lithic Torriorthents
    • Lithic Haplargids
  • Percent Slope 10 to 60 or more
  • Elevation 1,520 to 2,120 m (5,000 to 7,000 ft)
  • Mean Annual Precipitation 250 to 410 mm (10 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 70
  • Mean January Air Temperature -1 to 7 C (30 to 45 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 8 to 15 C (47 to 59 F)
  • Frost-Free Days 130 to 190
  • Area and Percent of State 596,330 ha (1,473,500 ac), 2.0
  • Land Uses rangeland, wildlife habitat, recreation and mining

This association consists of rock outcrop and well-drained, very shallow and shallow soils on hills, mountains, mesa escarpments and canyon walls throughout the Mesic Semiarid zone. The soils formed in residuum and colluvium weathered from volcanic, granitic and sedimentary rocks.

Lithic Torriorthents make up about 40 percent of the association, Lithic Haplargids 25 percent, rock outcrop 15 percent and minor areas of included moderately deep and deep soils formed in alluvium on fans and along drainageways 20 percent. Representative deep and moderately deep soils included in the association are Pastura, Lonti, Poley, Balon and Jacks on uplands, and Lynx, Tours, Cordes, Redbank and Rune along drainageways.

The dominant native vegetation is juniper, pinyon pine, shrub live oak, manzanita, ceanothus, mountainmahogany, grama grass, bluestem, western wheatgrass, Indian ricegrass, big sagebrush in some areas, needlegrass and threeawn.

Smoother areas of this association have good potential for grazing livestock. The steeper, stonier areas receive limited use by domestic livestock but are good habitat for deer and, in some areas, bighorn sheep.

Factors limiting the potential of these areas for community uses are steep slopes, shallow depth to bedrock and rock fragments on the surface. Selected areas are suitable for campgrounds, picnic areas and pack trails. Canyon de Chelly National Monument, a noted scenic attraction, is included in this association. A portion of the Black Mesa is used for surface-mined coal production. Both of these areas are on the Navajo and Hopi Indian reservations.


[page 129]

MS7 Cabezon-Thunderbird-Springerville Association

Shallow to deep, gravelly, cobbly and stony, fine-textured, nearly level to very steep soils on basaltic plains, mesas and hills.

  • Soil Classification
    • Lithic Argiustolls
    • Aridic Argiustolls
    • Typic Chromusterts
  • Percent Slope mostly none to 30; to 75 or more on escarpment-like areas and in canyons
  • Elevation 1,370 to 2,120 m (4,500 to 7,000 ft); some peaks to 2,430 m (8,000 ft)
  • Mean Annual Precipitation 300 to 510 mm (12 to 20 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 65
  • Mean January Air Temperature -1 to 7 C (30 to 45 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 8 to 15 C (47 to 59 F)
  • Frost-Free Days 120 to 180
  • Area and Percent of State 597,340 ha (1,476,000 ac), 2.0
  • Land Uses rangeland, wildlife habitat and recreation

This association consists of well-drained soils on plains, mesas, hills and very steep escarpments in scattered areas throughout the Mesic Semiarid zone. The soils formed in residuum and alluvium weathered from basalt and ash-flow tuffs, cinders and related volcanic materials.

Cabezon soils make up about 35 percent of the association, Thunderbird soils 30 percent, Springerville soils 15 percent and minor areas of associated soils and rock outcrop 20 percent. These included soils are mostly small areas of Venezia, Apache, Cross, Rudd, Waldroup and Ziegler on uplands, and narrow areas of Lynx and Jacques along drainageways.

The dominant native vegetation is blue, hairy and sideoats grama, tobosa, wolftail, algerita, ring muhly, squirreltail and juniper. Some pinyon and ponderosa pine grow in the areas that have high precipitation.

These soils have fair potential for production of livestock and wildlife forage. Domestic livestock avoid areas with broad fissures and areas with cobbly, stony surfaces.

The principal factors limiting the potential of these soils for development of homesites and recreation sites are high shrink-swell, clay textures, slow to very slow permeability and excessive rock fragments on the surface.


[page 130]

MS8 Pastura-Poley-Partri Association

Shallow, gravelly, medium-textured and deep fine-textured, nearly level to rolling soils on plains and hills.

  • Soil Classification
    • Ustollic Paleorthids
    • Ustollic Haplargids
    • Aridic Argiustolls
  • Percent Slope 1 to 15
  • Elevation 1,460 to 1,940 m (4,800 to 6,400 ft)
  • Mean Annual Precipitation 300 to 410 mm (12 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 65
  • Mean January Air Temperature -1 to 4 C (30 to 40 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature 10 to 14 C (50 to 57 F)
  • Frost-Free Days 135 to 175
  • Area and Percent of State 335,290 ha (828,500 ac), 1.1
  • Land Uses rangeland and wildlife habitat; some irrigated cropland on Poley soils

This association consists of well-drained soils on plains and hills. The soils formed on old alluvium weathered from limestone, sandstone and basalt.

Pastura soils make up about 35 percent of the association, Poley soils 35 percent, Partri soils 25 percent and minor areas of associated soils 5 percent. The included soils are mostly small areas of Showlow and Abra on uplands, and Rune, Cordes and Lynx along drainageways.

Small areas of Poley soils are used for irrigated cropland. The dominant native vegetation is blue, hairy, black and sideoats grama, wolftail, ring muhly, cane bluestem, squirreltail, winterfat and scattered juniper in some areas. Crops grown under irrigation are mostly feed grains, corn, alfalfa and pasture grasses.

These soils have good potential for producing livestock forage. Wildlife use, except by antelope, is transitory. The best cover is along drainageways.

The major factors limiting the potential of these soils for homesites and other community uses are shallow depth to hardpan and high lime in Pastura soils, and slow permeability, clay subsoils, high shrink-swell and low bearing strength in Poley and Partri soils.


[page 131]

MS9 Lonti-Balon-Lynx Association

Deep, moderately fine and gravelly, moderately fine and fine-textured, nearly level soils on floodplains and undulating to steep valley slopes and plains.

  • Soil Classification
    • Ustollic Haplargids
    • Cumulic Haplustolls
  • Percent Slope uplands, 1 to 45; floodplains, swales and lower fans, none to 5
  • Elevation 1,270 to 1,670 m (4,200 to 5,500 ft)
  • Mean Annual Precipitation 300 to 460 mm (12 to 18 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature 2 to 7 C (35 to 45 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 10 to 15 C (50 to 59 F)
  • Frost-Free Days 140 to 200
  • Area and Percent of State 128,290 ha (317,000 ac), 0.4
  • Land Uses rangeland and wildlife habitat; cropland, urban, recreation and placer mining on small areas of Lynx soils

This association consists of well-drained soils on dissected old alluvial fan surfaces and in swales and on floodplains. Lonti and Balon soils formed in mixed old alluvium, and Lynx soils in mixed recent alluvium, weathered mainly from granite, schist, sandstone, shale, limestone and volcanic rocks.

Lonti soils make up about 60 percent of the association, Balon soils 15 percent, Lynx soils 15 percent and minor areas of associated soils 10 percent. These minor soil areas are mostly Abra, Wineg and Springerville on the uplands and intermixed areas of Cordes on floodplains.

The dominant native vegetation is blue, hairy, black and sideoats grama, squirreltail, wolftail, muhly grasses, threeawn, shrub live oak, ceanothus, snakeweed and pubescent squawbush. Crops raised under irrigation are feed grains, corn, alfalfa and pasture grasses. There are a few small orchards.

These soils have good potential under good management for the production of range forage. Brush control and range seeding are practical on these soils. The best wildlife habitat is along drainageways.

The major factors limiting the potential of these areas for urban and recreational development are the flooding hazard on Lynx soils; moderately slow to slow permeability of all soils; high shrink-swell and low bearing strength of Lonti soils; and excessive slope and erosion hazard on some Balon and Lonti soils.


[page 132]

MS10 Pastura-Abra-Lynx Association

Shallow, gravelly, medium-textured and deep, medium and moderately fine-textured, nearly level to rolling soils on plains and hills.

  • Soil Classification
    • Ustollic Paleorthids
    • Ustollic Calciorthids
    • Cumulic Haplustolls
  • Percent Slope uplands, 1 to 30; floodplains and swales, none to 5
  • Elevation 1,340 to 1,700 m (4,400 to 5,600 ft)
  • Mean Annual Precipitation 280 to 410 mm (11 to 16 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature -1 to 4 C (30 to 40 F)
  • Mean July Air Temperature 21 to 27 C (70 to 80 F)
  • Mean Annual Soil Temperature 12 to 14 C (53 to 58 F)
  • Frost-Free Days 140 to 170
  • Area and Percent of State 96,120 ha (237,500 ac), 0.3
  • Land Uses rangeland and wildlife habitat; cropland, urban and recreation on small areas of Lynx soils

This association consists of well-drained, limy soils on nearly level to undulating plains, undulating to rolling ridges and hill toeslopes in the Chino Valley and adjacent area. Pastura and Abra soils formed in mixed old alluvium, and Lynx soils in recent alluvium, both weathered from limestone, sandstone, shale, granite, schist and volcanic rocks.

Pastura soils make up about 35 percent of the association, Abra soils 35 percent, Lynx soils 20 percent and minor areas of Lonti, Poley and Wineg soils 10 percent.

The dominant native vegetation is blue, hairy, black and sideoats grama, squirreltail, wolftail, muhly grasses, threeawn, shrub live oak, ceanothus, snakeweed and pubescent squawbush. Juniper and pinyon pine grow in some areas. Crops raised under irrigation are small grain, corn, alfalfa and pasture grasses.

This association has good potential for the production of range forage. Brush control and range seeding are possible on these soils. Juniper eradication is practical on the Pastura and Abra soils. These soils have good potential for rangeland wildlife habitat improvement, such as range seeding and water developments.

The major factors limiting the potential of these areas for development of homesites and recreation facilities are the possible flooding and the moderately slow permeability of Lynx soils; high lime content of Abra and Pastura soils and shallow depth to hardpan in Pastura soils; and excessive slope in some areas of Abra and Pastura soils.


[page 133]

7.2.6. Mesic Subhumid Soils

FIGURE 52. Representative Mesic Subhumid Soils Soilscape and Profiles (D. M. Hendricks)


[page 134]

FIGURE 53. Geographic Distribution of Mesic Subhumid (MH) Soils in Arizona (D. M. Hendricks)

MH1 Casto-Martinez-Canelo Association
MH2 Lithic Haplustolls-Lithic Argiustolls-Rock Outcrop Association
MH3 Showlow-Disterheff-Cibeque Association
MH4 Roundtop-Tortugas-Jacks Association
MH5 Overgaard-Elledge-Telephone Association
MH6 Pachic Argiustolls-Lynx Association

MH Mesic Subhumid Soils

Mesic Subhumid Soils have a mean annual soil temperature of 8 C (47 F) or more, but less than 15 C (59 F). The difference between mean summer and mean winter temperatures is greater than 5 C (9 F). The mean annual precipitation is more than 410 mm (16 in). These soils are at intermediate elevations. They cover about 2,021,270 ha (4,994,500 ac), or 7 percent of Arizona.


[page 135]

MH1 Casto-Martinez-Canelo Association

Deep, very fine-textured and deep, gravelly, moderately fine and fine-textured, nearly level to steep soils on dissected fan surfaces and valley slopes.

  • Soil Classification
    • Udic Haplustalfs
    • Udic Paleustalfs
    • Aquic Haplustalfs
  • Percent Slope 2 on mesas to 40 on sides of ridges and mesas; vertical relief 8 to 60 m (25 to 200 ft)
  • Elevation 1,670 to 1,880 m (5,500 to 6,200 ft)
  • Mean Annual Precipitation 410 to 510 mm (16 to 20 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 30 to 35
  • Mean January Air Temperature 4 to 7 C (40 to 45 F)
  • Mean July Air Temperature 18 to 24 C (65 to 75 F)
  • Mean Annual Soil Temperature 12 to 15 C (54 to 59 F)
  • Frost-Free Days 150 to 180
  • Area and Percent of State 28,530 ha (70,500 ac), 0.1
  • Land Uses rangeland, wildlife habitat and recreation

This association consists of deep, well-drained and somewhat poorly drained soils on high, dissected old alluvial fans. The soils formed in old alluvium derived from sedimentary and igneous rocks. The fan remnants range from long, narrow, rounded ridges with moderately steep slopes to fairly broad-topped, gently sloping mesas with steep side slopes.

Casto soils make up about 60 percent of the association, Martinez soils 20 percent, Canelo soils 15 percent and minor areas of White House soils on uplands and Comoro and Grabe soils in drainageways about 5 percent.

The dominant native vegetation on Casto and Canelo soils is Emory oak, pinyon pine, juniper, manzanita, Arizona cottontop, Texas and cane bluestem, grama grasses, curlymesquite, wolftail and perennial forbs. Martinez soils mostly have the same grasses but not the woody species.

This association has good potential for the production of livestock and wildlife forage. Brush control and range seeding are possible, where needed, on these soils. The principal kinds of wildlife are deer, antelope, quail, javelina, rabbits and some coatimundi. Parker Canyon Lake, in this unit, is stocked with bass, catfish and trout.

The principal factors limiting the potential of these soils for homesites, community uses and recreation sites are slow or very slow permeability and clayey texture in all soils, and excessive rock fragment content and slope on the Casto and Canelo soils.


[page 136]

MH2 Lithic Haplustolls-Lithic Argiustolls-Rock Outcrop Association

Shallow, gravelly and cobbly, moderately coarse to moderately fine-textured, gently sloping to very steep soils and rock outcrop on hills and mountains.

  • Soil Classification
    • Lithic Haplustolls
    • Lithic Argiustolls
  • Percent Slope mostly 5 to 60
  • Elevation central, 1,370 m (4,500 ft); southern, 2,135 m (7,000 ft)
  • Mean Annual Precipitation 410 to 630 mm (16 to 25 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 30 to 60
  • Mean January Air Temperature 2 to 7 C (35 to 45 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 8 to 15 C (47 to 59 F)
  • Frost-Free Days 140 to 230
  • Area and Percent of State 1,147,320 ha (2,835,000 ac), 3.9
  • Land Uses rangeland, wildlife habitat, water supply and recreation

This association consists of rock outcrop and dark-colored, well-drained, shallow and very shallow soils formed in the residuum on igneous and sedimentary hills and mountains.

Lithic Haplustolls make up about 50 percent of the association, Lithic Argiustolls 20 percent, rock outcrop 15 percent and minor areas of other shallow, moderately deep and deep soils 15 percent.

Faraway, Tortugas and the similar Barkerville soils are representative of Lithic Haplustolls. Luzena and Cabezon soils are representative Lithic Argiustolls. Cross, Gaddes, Mokiak and Moano soils on uplands and Cordes and Lynx soils along drainageways are some of the minor included soils.

The dominant native vegetation is oak, juniper, pinyon pine, manzanita, cliffrose, grama grasses, plains lovegrass, Texas and cane bluestem, tanglehead and galleta. Some ponderosa and other pine trees grow above 1,670 m (5,500 ft). These soils have fair to good potential for the production of livestock forage on much of the association. Wildlife commonly observed on the association include white- and blacktail deer, bighorn sheep, quail, dove, rabbits, squirrel, wild turkey and small rodents and birds.

The dominant factors limiting the potential of these areas for the development of homesites and other community and recreational uses are excessive slope, excessive rock fragments on the surface and shallow depth to bedrock. Small areas on the fans and drainageways may be suitable for campsite and picnic areas.


[page 137]

MH3 Showlow-Disterheff-Cibeque Association

Deep, gravelly, medium and fine-textured, nearly level to steep soils on dissected uplands.

  • Soil Classification
    • Aridic Argiustolls
    • Typic Haplustalfs
    • Ustollic Calciorthids
  • Percent Slope plains, 2 to 20; dissected uplands, to 60
  • Elevation 1,370 to 2,030 m (4,500 to 6,700 ft)
  • Mean Annual Precipitation 410 to 560 mm (16 to 22 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 55
  • Mean January Air Temperature -1 to 4 C (30 to 40 F)
  • Mean July Air Temperature 16 to 24 C (60 to 75 F)
  • Mean Annual Soil Temperature 8 to 15 C (47 to 59 F)
  • Frost-Free Days 115 to 170
  • Area and Percent of State 227,440 ha (562,000 ac), 0.8
  • Land Uses rangeland, woodland, wildlife habitat, water supply and recreation

This association consists of well-drained soils in narrow valleys and on plains and dissected uplands on the Mogollon Plateau and in other small areas. The soils formed in mixed gravelly old alluvium derived from sedimentary and some volcanic rocks.

Showlow soils make up about 35 percent of the association, Disterheff soils 35 percent, Cibeque soils 20 percent and minor areas of associated soils 10 percent. These minor soils are mostly small areas of Elledge, Chevelon and Millard on uplands and narrow areas of Lynx, Jaques, Tours and Zeniff along drainageways.

A few small areas of Showlow soils were dry farmed in the past. Corn, small grain and grain sorghum were produced but crop failure due to lack of moisture was common. The dominant native vegetation is juniper, pinyon pines, shrub live oak, cliffrose, mountainmahogany, grama grasses, western wheatgrass and muhly grasses. Ponderosa pine grows at high elevations and on the north and east aspects at lower elevations.

These soils have only fair potential for the production of livestock forage due to the competition of woody species. Grazing use is mainly during the summer months. They have good potential for woodland and rangeland wildlife habitat. Dominant wildlife species are deer, squirrel, Wild Turkey and elk at some high elevations, rabbits, quail, dove and small rodents and birds.

The major factors limiting the potential of these soils for homesites, community uses and recreation sites are the slow permeability and high shrink-swell potential of the Showlow and Disterheff soils, excessive slope of the Cibeque and some Disterheff soils and high lime in the Cibeque soils. Smooth areas of Showlow and Disterheff soils are suitable for campgrounds and picnic areas. Hunting, fishing and camping are good in many areas of this association.


[page 138]

MH4 Roundtop-Tortugas-Jacks Association

Shallow to moderately deep, gravelly and cobbly, medium and fine-textured, undulating to very steep soils on hills and mountains.

  • Soil Classification
    • Aridic Argiustolls
    • Lithic Haplustolls
    • Udic Haplustalfs
  • Percent Slope 2 to 60 or more
  • Elevation 1,370 to 2,060 m (4,500 to 6,800 ft)
  • Mean Annual Precipitation 410 to 630 mm (16 to 25 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature -1 to 7 C (30 to 45 F)
  • Mean July Air Temperature 21 to 29 C (70 to 85 F)
  • Mean Annual Soil Temperature 8 to 15 C (47 to 59 F)
  • Frost-Free Days 120 to 170
  • Area and Percent of State 413,600 ha (1,022,000 ac), 1.4
  • Land Uses rangeland, woodland, wildlife habitat, water supply and recreation

This association consists of well-drained soils on limestone and sandstone mountains just south of the Mogollon Rim.

Roundtop soils make up about 35 percent of the association, Tortugas soils 35 percent, Jacks soils 15 percent and minor areas of rock outcrop and associated soils 15 percent. The minor soils are mostly small areas of Dye, Rond, Telephone and Barkerville on uplands, and narrow areas of Tours, Lynx and Jacques along drainageways.

The dominant native vegetation is pinyon pine, juniper, Gambel oak, manzanita, shrub live oak, ceanothus, cliffrose, mountainmahogany, grama and muhly grasses, western wheatgrass, wolftail, squirreltail and pine dropseed. Ponderosa pine grows at high elevations and on north and east aspects at lower elevations.

These soils have only fair potential for the production of livestock forage due to the competition from woody species. Brush control is practical on the smoother areas. The association has good potential for woodland and rangeland wildlife habitat. The dominant wildlife species are deer, squirrel, turkey and elk at some high elevations, rabbits, quail, dove and small rodents and birds.

The major factors limiting the potential of these soils for homesites, community uses and recreation sites are shallow and moderate depths to bedrock and slow permeability of Roundtop and Jacks soils and steep slopes in some areas of all soils. Smooth areas of Jacks soils and some of the included soils are suitable for campgrounds and picnic areas. Hunting, fishing and camping are good in many areas of this association. Several large Indian ruins are in the area.


[page 139]

MH5 Overgaard-Elledge-Telephone Association

Shallow to deep, gravelly and cobbly, moderately coarse and fine-textured, undulating to very steep soils on mountains and hills.

  • Soil Classification
    • Typic Haplustalfs
    • Udic Haplustalfs
    • Lithic Ustorthents
  • Percent Slope 2 to 60 or more
  • Elevation 1,670 to 2,340 m (5,500 to 7,700 ft)
  • Mean Annual Precipitation 460 to 630 mm (18 to 25 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 50
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 18 to 21 C (65 to 70 F)
  • Mean Annual Soil Temperature 7 to 13 C (45 to 56 F)
  • Frost-Free Days 110 to 150
  • Area and Percent of State 179,280 ha (443,000 ac), 0.6
  • Land Uses forestry, rangeland, water supply, wildlife habitat and recreation

This association consists of well-drained soils on the forested highlands along the Mogollon Rim and the deeply dissected breaks along the Rim's south edge. The soils formed in residuum and colluvium weathered from sandstone, cherty limestone and shale.

Overgaard soils make up about 35 percent of the association, Elledge soils 30 percent, Telephone soils 25 percent and minor areas of associated soils and rock outcrop 10 percent. The minor included soils are mostly Amos, Showlow, Jacks, Tortugas and Roundtop on uplands, and Lynx, Tours and Jocity along drainageways.

The dominant vegetation is ponderosa and pinyon pine, Gambel oak, juniper, mountainmahogany, manzanita, mountain muhly, grama grasses, Arizona fescue, little bluestem, junegrass, pine dropseed and western wheatgrass.

Timber is harvested in the more accessible areas. The association has low potential for domestic livestock forage production due to steep slopes and competition from woody species. Most grazing is during the summer months. The potential is good for woodland wildlife habitat. The dominant game species are deer, elk, black bear, wild turkey, mountain lion, squirrel and Band-tailed Pigeon. Camping, hunting and fishing are good in this association.

The major factors limiting the potential of these soils for homesites, community uses and recreation are excessive slope on much of the area, moderate and shallow depth to bedrock in the Elledge and Telephone soils, and slow permeability in Overgaard and Elledge soils. All of these soils are subject to moderate frost action. Smooth and less sloping areas of Overgaard and Elledge soils and some of the included minor soils are suitable for campgrounds and picnic areas.


[page 140]

MH6 Pachic Arguistolls-Lynx Association

Deep, moderately fine and fine-textured, nearly level to gently rolling soils on plains.

  • Soil Classification
    • Pachic Argiustolls
    • Cumulic Haplustolls
  • Percent Slope mostly 2 to 8; range is 2 to 15
  • Elevation 1,760 to 2,000 m (5,800 to 6,600 ft)
  • Mean Annual Precipitation 410 to 510 mm (16 to 20 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 50
  • Mean January Air Temperature -1 to 2 C (30 to 35 F)
  • Mean July Air Temperature 21 to 24 C (70 to 75 F)
  • Mean Annual Soil Temperature 8 to 12 C (47 to 54 F)
  • Frost-Free Days 115 to 150
  • Area and Percent of State 25,090 ha (62,000 ac), less than 0.1
  • Land Uses rangeland, wildlife habitat and recreation

This association consists of well-drained soils of the Big Prairie area near Point of Pines on the San Carlos Apache Indian Reservation. The soils formed in mixed old and recent alluvium weathered from basalt, tuffs and agglomerates.

Pachic Argiustolls (Showlow-like soils) make up about 55 percent of the association, Lynx soils 30 percent and minor areas of associated soils and rock outcrop 15 percent. The included soils are mostly small areas of Thunderbird, Cabezon and Faraway on uplands and small areas of Cordes intermixed with Lynx along drainageways.

The dominant native vegetation is grass with scattered ponderosa and pinyon pine and juniper. Grasses are sideoats, blue and hairy grama, tobosa, Arizona fescue, muhly grasses and western wheatgrass.

This association has good potential for producing livestock forage. Some areas are overgrazed due to easy accessibility. The potential for rangeland wildlife habitat is good. Dominant species are antelope, elk (winter range), quail, dove, rabbits and small mammals and birds. Several small, trout-stocked lakes are in the area.

Factors limiting the potential of these soils for development of homesites and recreation sites are moderately slow and slow permeability and possible brief flooding on some areas of Lynx soils. In addition, the Arguistolls have high shrink-swell in the subsoil.

7.2.7. FH Frigid Subhumid Soils


[page 141]

FIGURE 54. Representative Frigid Subhumid Soils Soilscape and Profiles (D. M. Hendricks)


[page 142]

FIGURE 55. Geographic Distribution of Frigid Subhumid (FH) Soils in Arizona (D. M. Hendricks)

FH1 Mirabal-Dandrea-Brolliar Association
FH2 Sponseller-Ess-Gordo Association
FH3 Soldier-Hogg-McVickers Association
FH4 Soldier-Lithic Cryoborolls Association
FH5 Mirabal-Baldy-Rock Outcrop Association
FH6 Eutroboralfs-Mirabal Association
FH7 Cryorthents-Eutroboralfs Association
FH8 Gordo-Tatiyee Association

FH Frigid Subhumid Soils

Frigid Subhumid Soils have mean annual soil temperatures lower than 8 C (47 F). The difference between mean winter and mean summer soil temperataure is more than 5 C (9 F) at a depth of 50 cm (20 in) or at a bedrock contact in shallow soils. The mean annual precipitation is more than 410 cm (16 in), with one-half or more usually falling during the winter and early spring months as snow, sleet or rain. These soils are at elevations mostly more than 1,970 m (6,500 ft) on the Colorado Plateau and in a few of the high mountains of the Basin and Range Province. They cover about 2,093,110 ha (5,172,000 ac), or 7 percent of Arizona.


[page 143]

FH1 Mirabal-Dandrea-Brolliar Association

Moderately deep and deep, gravelly and cobbly, moderately coarse and fine-textured, gently sloping to very steep mountain soils.

  • Soil Classification
    • Typic Ustorthents
    • Mollic Eutroboralfs
    • Typic Argiborolls
  • Percent Slope mountain and mesa tops, 1 to 15; mountainsides and canyons, 15 to 60 or more
  • Elevation 1,820 to 2,430 m (6,000 to 8,000 ft)
  • Mean Annual Precipitation 460 to 760 mm (18 to 30 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature 2 to 7 C (35 to 45 F)
  • Mean July Air Temperature 18 to 27 C (65 to 80 F)
  • Mean Annual Soil Temperature 6 to 11 C (43 to 52 F)
  • Frost-Free Days 80 to 170
  • Area and Percent of State 37,430 ha (92,500 ac), 0.1
  • Land Uses grazable woodland, wildlife habitat, recreation, water supply and some mining

This association consists of well-drained soils on high mountains. The soils formed in residuum on granite and schist mountains and high basalt mesas.

Mirabal soils make up about 50 percent of the association, Dandrea soils 25 percent, Brolliar soils 10 percent and rock outcrop and minor areas of associated soils 15 percent. These minor soils are mostly small areas of Hogg and Wilcoxson on uplands and narrow areas of Clover Springs and Luth along drainageways.

The dominant native vegetation is ponderosa pine, Gambel oak, Douglas fir and some quaking aspen at high elevations. The grass understory is mostly Arizona fescue, mountain muhly, mountain brome and squirreltail. Most livestock grazing use is during summer months. Timber is harvested in some areas of this association. The principal wildlife species are deer, Wild Turkey, porcupine, Abert's squirrel, Band-tailed Pigeon, black bear and mountain lion. A few dove and rabbits are in the aspen areas.

Factors limiting the potential of these soils for the development of summer homesites and recreation sites are slope, depth to bedrock and potential frost action on all soils, and slow permeability and high shrink-swell on Brolliar and Dandrea soils. Smooth, gently sloping areas of these soils are suitable for campgrounds and picnic sites. Hunting, hiking and winter sports and camping are the main recreational activities.


[page 144]

FH2 Sponseller-Ess-Gordo Association

Moderately deep and deep, medium and moderately fine-textured, moderately sloping to very steep mountain soils.

  • Soil Classification
    • Typic Argiborolls
    • Argic Pachic Cryoborolls
  • Percent Slope 5 to 60 or more
  • Elevation 2,000 to 3,790 m (6,600 to 12,500 ft)
  • Mean Annual Precipitation 460 to 760 mm (18 to 30 in) or more
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 65
  • Mean January Air Temperature -4 to 4 C (25 to 40 F)
  • Mean July Air Temperature 16 to 27 C (60 to 80 F)
  • Mean Annual Soil Temperature 3 to 8 C (38 to 47 F)
  • Frost-Free Days 70 to 125
  • Area and Percent of State 1,280,670 ha (3,164,500 ac), 4.3
  • Land Uses grazable woodland, wildlife habitat, recreation and water supply

This association consists of well-drained soils on high mountains. The soils formed in residuum and colluvium weathered from basalt, rhyolite, andesite, cinders, ash-flow tuff and related volcanic rocks.

Sponseller soils make up about 25 percent of the association, Ess soils 25 percent, Gordo soils 25 percent and minor areas of a large number of associated and similar soils 25 percent. The minor associated soils include small areas of Cambern, Baldy, Bushvalley, Brolliar, Mirabal, Siesta, Sizer, Clover Springs, Luth and several uncorrelated soils mapped by the U.S. Forest Service. Small areas of rock outcrop and talus slope on peaks also are included.

The dominant native vegetation is ponderosa pine, Douglas fir, spruce, quaking aspen, juniper and Gambel oak. Grasses occur in small open areas and consist of Arizona fescue, pine dropseed, junegrass, wheatgrass, mountain muhly, squirreltail and brackenfern. Most livestock grazing is during summer months. The potential for timber production is fair to good. The potential for woodland wildlife habitat management also is good. The dominant wildlife species are deer, elk, Wild Turkey, Abert's squirrel, black bear, mountain lion, porcupine, Band-tail Pigeon and a few dove and cottontail rabbits. Several large trout-stocked lakes are in the mapping unit. Recreation uses are hunting, fishing, hiking, camping and skiing.

The major factors limiting the potential of these soils for building sites and recreational facilities are moderately slow permeability, potential frost action, rock fragments on the surface and slope. Smooth, gently sloping areas can be used for campgrounds, picnic sites and other community uses.


[page 145]

FH3 Soldier-Hogg-McVickers Association

Moderately deep and deep, fine-textured, gently sloping to steep mountain soils.

  • Soil Classification
    • Typic Glossoboralfs
    • Mollic Eutroboralfs
    • Typic Eutroboralfs
  • Percent Slope mostly 2 to 20; range is 2 to 50
  • Elevation 2,000 to 2,730 m (6,600 to 9,000 ft)
  • Mean Annual Precipitation 460 to 760 mm (18 to 30 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature -1 to 4 C (30 to 40 F)
  • Mean July Air Temperature 18 to 21 C (65 to 70 F)
  • Mean Annual Soil Temperature 5 to 8 C (41 to 47 F)
  • Frost-Free Days 85 to 125
  • Area and Percent of State 192,430 ha (475,500 ac), 0.7
  • Land Uses grazable woodland, forestry, wildlife habitat, recreation and water supply

This association consists of moderately well- and well-drained soils on high mountainous areas on the Coconino Plateau and adjacent areas. The soils formed in residuum weathered from cherty limestone and sandstone, members of the Kaibab and Coconino geologic formations.

Soldier soils make up about 55 percent of the association, Hogg soils 20 percent, McVickers soils 15 percent and minor areas of associated soils and rock outcrop 10 percent. The included minor soils are mostly small areas of Overgaard, Wildcat, Sanchez, Chilson and Palomino on uplands, and narrow areas of Clover Springs and Luth along drainageways.

The dominant native vegetation is ponderosa pine, Douglas and white fir, quaking aspen and some Gambel oak, juniper and ceanothus. Grasses in open areas and as understory include Arizona fescue, pine dropseed, squirreltail, blue grama, junegrass and brackenfern. These areas are some of the best timber-producing soils in the state. Most livestock grazing is during summer months. The potential for woodland wildlife habitat management is good. The dominant wildlife species are deer, elk, black bear, mountain lion, Wild Turkey, Band-tailed Pigeon, dove, porcupine, and small birds and rodents. Lake Mary and Mormon Lake are the largest lakes in the area and are stocked with fish at times.

The dominant factors limiting the potential of these soils for homesites and recreation facilities are slow permeability, high shrink-swell, moderate frost-action potential and depth to bedrock. Some areas have excessive slope.


[page 146]

FH4 Soldier-Lithic Cryoborolls Association

Shallow and deep, medium to fine-textured, gently sloping to steep mountain soils.

  • Soil Classification
    • Typic Glossoboralfs
    • Lithic Cryoborolls
  • Percent Slope mostly 2 to 30; range to 50
  • Elevation 2,000 to 2,730 m (6,600 to 9,000 ft)
  • Mean Annual Precipitation 410 to 760 mm (16 to 30 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 70
  • Mean January Air Temperature -4 to 7 C (25 to 45 F)
  • Mean July Air Temperature 16 to 29 C (60 to 85 F)
  • Mean Annual Soil Temperature 5 to 8 C (41 to 47 F)
  • Frost-Free Days 85 to 125
  • Area and Percent of State 210,440 ha (520,000 ac), 0.7
  • Land Uses timber production, grazable woodland, wildlife habitat, recreation and water supply

This association consists of moderately well-drained and well-drained soils on the higher part of the Kaibab Plateau. The soils formed in residuum weathered from calcareous sandstone and limestone.

Soldier soils make up about 65 percent of the association, Lithic Cryoborolls 15 percent and rock outcrop and minor areas of associated and similar soils 20 percent. These included soils are mostly small areas of Palomino on uplands and Luth and Clover Springs on narrow floodplains along drainageways.

The dominant native vegetation is ponderosa pine. Douglas and white fir, Gambel oak and quaking aspen, with an understory of Arizona fescue, junegrass, mountain muhly, muttongrass and pine dropseed. Soldier soils are considered to be the best pine-fir producing soils in the state. Most livestock grazing is during summer months. The potential for woodland wildlife management is good. The dominant wildlife species are mule deer, grouse, mountain lion, Wild Turkey, Band-tailed Pigeon, squirrels, porcupine and small birds and rodents.

Factors limiting the potential of these soils for development of homesites and recreation areas are the shallow depth to bedrock and steep slopes of the Lithic Cryoborolls. Also, the Soldier soils have high shrink-swell and very slow permeability, which is poor for use as septic tank absorption fields. Smooth, gently sloping areas can be used for campgrounds and picnic areas.


[page 147]

FH5 Mirabal-Baldy-Rock Outcrop Association

Shallow to deep, gravelly and cobbly, moderately coarse-textured, hilly to very steep mountain soils and rock outcrop.

  • Soil Classification
    • Typic Ustorthents
    • Typic Cryorthents
  • Percent Slope 5 to 70
  • Elevation 2,060 to 3,280 m (6,800 to 10,800 ft)
  • Mean Annual Precipitation 410 to 760 mm (18 to 30 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 50 to 60
  • Mean January Air Temperature -1 to 4 C (30 to 40 F)
  • Mean July Air Temperature 18 to 27 C (65 to 80 F)
  • Mean Annual Soil Temperature 4 to 8 C (40 to 47 F)
  • Frost-Free Days 80 to 125
  • Area and Percent of State 101,380 ha (250,500 ac), 0.3
  • Land Uses grazable woodland, recreation, wildlife habitat and water supply

This association consists of well-drained soils and rock outcrop on high mountain ranges. The soils formed in residuum weathered from granite, gneiss, schist and other igneous rocks.

Mirabal soils make up about 30 percent of the association, Baldy soils 30 percent, rock outcrop 20 percent and minor areas of associated soils 20 percent. The included minor soils are unnamed and uncorrelated and range from shallow to deep, gravelly to very stony and moderately coarse to moderately fine-textured.

The dominant vegetation is ponderosa and limber pine, Douglas fir, quaking aspen, Gambel and silverleaf oak, mountain brome, Arizona fescue, mountain muhly and junegrass. Some areas are used for timber production. Most livestock grazing is during summer months. Both summer and winter recreation activities are enjoyed in most areas, including hiking, skiing, camping and fishing. The potential for woodland wildlife habitat management is good. The dominant wildlife species are whitetail and mule deer, Wild Turkey, black bear, mountain lion, Abert's and Arizona gray squirrels, porcupine, Band-tailed Pigeon, Gambel's and Scale Quail and small birds and rodents.

Factors limiting the potential of these soils for homesite and campground development are shallow depth to rock and steep slopes. Smooth, gently sloping areas can be used for campgrounds, picnic sites and other community uses.


[page 148]

FH6 Eutroboralfs-Mirabal Association

Shallow to deep, cobbly, moderately coarse and gravelly fine-textured, gently sloping to very steep mountain soils.

  • Soil Classification
    • Typic Eutroboralfs
    • Typic Ustorthents
  • Percent Slope 5 to 75
  • Elevation 2,060 to 2,760 m (6,800 to 9,100 ft)
  • Mean Annual Precipitation 410 to 630 mm (16 to 25 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 50
  • Mean January Air Temperature -1 to 4 C (30 to 40 F)
  • Mean July Air Temperature 18 to 24 C (65 to 75 F)
  • Mean Annual Soil Temperature 5 to 8 C (42 to 47 F)
  • Frost-Free Days 70 to 110
  • Area and Percent of State 62,730 ha (155,000 ac), 0.2
  • Land Uses grazable woodland, recreation, wildlife habitat and water supply

This association consists of well-drained soils on high mountains. The soils formed in residuum and alluvium weathered from volcanic, granitic and other igneous rocks and sandstone.

The Eutroboralfs make up about 60 percent of the association, Mirabal soils 30 percent and rock outcrop and minor areas of associated soils 10 percent.

The dominant vegetation is ponderosa and pinyon pine, juniper, Douglas and white fir and some spruce and quaking aspen on north slopes at high elevations. The understory is mountain muhly, mountain brome, grama grasses, Arizona fescue, pine dropseed and junegrass. Most livestock grazing is during summer months. Timber is harvested in a few areas. Recreation includes camping, hiking, hunting and fishing. The principal wildlife species are deer, elk, black bear, mountain lion, Wild Turkey, quail, Band-tailed Pigeon, squirrels, porcupines and small birds and rodents.

Factors limiting the potential of these soils for homesite and campground development are high cobble content and shallow depth to rock in the Mirabal soils. Also the Eutroboralfs have slow permeability, which is poor for use as septic tank absorption fields. Both Mirabal and Eutroboralf soils have steep slopes.


[page 149]

FH7 Cryorthents-Eutroboralfs Association

Shallow to deep, moderately coarse to fine-textured, gently sloping to steep, high mountain soils.

  • Soil Classification
    • Cryorthents
    • Eutroboralfs
  • Percent Slope 2 to 50
  • Elevation 2,120 to 2,970 m (7,000 to 9,800 ft)
  • Mean Annual Precipitation 410 to 560 mm (16 to 22 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 55 to 60
  • Mean January Air Temperature -4 to -1 C (25 to 30 F)
  • Mean July Air Temperature 21 to 24 C (70 to 75 F)
  • Mean Annual Soil Temperature 5 to 8 C (41 to 47 F)
  • Frost-Free Days 85 to 110
  • Area and Percent of State 171,190 ha (423,000 ac), 0.6
  • Land Uses livestock grazing, wildlife habitat, recreation and some timber production

This association consists of well-drained soils at high elevations on the Chuska and Lukachukai mountains. The soils formed in residuum weathered from sandstone, limestone, shale, conglomerate and volcanic rocks.

Soil series have not been assigned to soils in this mostly unsurveyed area. It is estimated that medium and moderately fine-textured Cryorthents make up about 40 percent of this association, fine and moderately fine-textured Eutroboralfs 40 percent and rock outcrop and shallow or very shallow soils over sandstone or shale bedrock 20 percent.

The dominant vegetation is ponderosa and pinyon pine, juniper and Gambel oak. Understory grasses include mountain muhly, pine dropseed, Arizona fescue, squirreltail and western wheatgrass. This unit is the primary source of commercial timber for the Navajo Indian Reservation in Arizona. Sheep, goats and cattle graze accessible areas during warmer months. The principal wildlife species are deer, mountain lion, Wild Turkey, grouse, quail, squirrel, marmot and small birds and rodents.

Factors limiting the potential of these soils for homesite and campground development are shallow depth to rock and moderately slow to slow permeability, which is poor for use as septic tank absorption fields.


[page 150]

FH8 Gordo-Tatiyee Association

Deep and moderately deep, gravelly, medium to fine-textured, nearly level to rolling soils of the mountain meadows.

  • Soil Classification
    • Argic Pachic Cryoborolls
    • Argic Cryoborolls
  • Percent Slope none to 15
  • Elevation 2,300 to 3,030 m (7,600 to 10,000 ft)
  • Mean Annual Precipitation 460 to 760 mm (18 to 30 in)
  • Winter Precipitation as the Percentage of Annual Precipitation 45 to 50
  • Mean January Air Temperature -4 to -1 C (25 to 30 F)
  • Mean July Air Temperature 16 to 21 C (60 to 70 F)
  • Mean Annual Soil Temperature 3 to 8 C (38 to 47 F)
  • Frost-Free Days 70 to 110
  • Area and Percent of State 36,830 ha (91,000 ac), 0.1
  • Land Uses summer grazing of livestock, water supply, wildlife habitat and recreation

This association consists of well-drained soils in high mountain meadows near Big Lake and Green's Peak the soils formed in residuum weathered from basalt, cinders and ash.

Gordo soils make up about 45 percent of the association, Tatiyee soils 40 percent and small areas of stony, shallow soils on basalt, and narrow areas of Luth and Clover Springs along drainageways and depressions make up about 15 percent.

Several large trout-stocked lakes are within this unit, and one ski run is nearby. The dominant native vegetation is grass, and includes Arizona fescue, Kentucky bluegrass, mountain muhly, sedges, weeds and native flowers. Some areas have big sagebrush, bitterbrush, bluebunch wheatgrass and mutton bluegrass. The dominant wildlife species using this association are elk, deer, Wild Turkey, badger and small rodents.

Factors limiting the potential of these soils for homesite and campground development are the high shrink-swell and slow permeability of the Tatiyee soils, which is poor for use as septic tank absorption fields. Both Tatiyee and Gordo soils are gravelly and cobbly.


Notes

5. *This association has been correlated Oracle-Romero Association since the field work for the state general map was completed.

6. *Soils originally called Karro in the San Simon area were correlated Hondale

7. Bandera soils are in a frigid temperature class.

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