LOCATION TOMARIZO AZEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Lithic Haplustalfs
TYPICAL PEDON: Tomarizo very gravelly sandy loam - recreation and wildlife habitat. (Colors are for dry soil unless otherwise noted.)
A--0 to 4 inches; brown (7.5YR 4/2) very gravelly sandy loam, very dark brown (7.5YR 2.5/2) moist; moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; few very fine roots; few very fine and fine irregular pores; 30 percent gravel, 10 percent cobble; noneffervescent, slightly acid (pH 6.4); abrupt smooth boundary. (3 to 4 inches thick)
Bt1--4 to 9 inches; brown (7.5YR 5/4) very gravelly sandy clay loam, dark brown (7.5YR 3/4) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine and medium roots; common very fine and fine irregular and few fine tubular pores; common faint clay films on faces of peds and in pores; 40 percent gravel, 15 percent cobble; noneffervescent; slightly acid (pH 6.2); clear smooth boundary.
Bt2--9 to 12 inches; brown (7.5YR 5/4) extremely gravelly sandy clay loam, dark brown (7.5YR 3/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine and medium roots; common fine irregular and few fine and medium tubular pores; 40 percent gravel, 20 percent cobble; common faint and few distinct clay films on faces of peds and in pores; noneffervescent; slightly acid (pH 6.2); abrupt irregular boundary. (Combined thickness of the Bt horizons is 4 to 12 inches)
R--12 inches; hard, dacitic breccia with few very fine fractures between the lithic clasts and tuffaceous matrix, fractures are fine enough to generally exclude roots.
TYPE LOCATION: Coronado National Memorial; located at a latitude of 31 degrees, 21 minutes, 03 seconds North and longitude of 110 degrees, 16 minutes, 46 seconds West.
RANGE IN CHARACTERISTICS:
Soil moisture: Intermittently moist in some part of the soil moisture control section during July - September and December - February. Driest during May and June. Aridic ustic soil moisture regime.
Soil Temperature: 59 to 64 degrees F.
Rock fragments: 35 to 60 percent
Depth to bedrock: 7 to 16 inches
Reaction: slightly acid or moderately acid
Clay content: averages 18 to 27 percent
Organic Matter: 1 to 3 percent in the surface layer
A horizon
Hue: 7.5YR, 5YR
Value: 4 or 5 dry
Chroma: 2 or 3, dry or moist
Bt horizon
Hue: 7.5YR, 5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4, dry or moist
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Tomarizo soils are on hill and mountain side slopes at elevations of 5600 to 6800 feet. Slopes range from 30 to 50 percent. These soils formed in colluvium and residuum from dacitic breccia. The mean annual precipitation is 18 to 23 inches and occurs as thunderstorms during July to September and as gentle rains during December and January. The mean annual air temperature is 57 to 62 degrees F. The frost-free period is 160 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Canquya (AZ) and Yarbam (AZ) soils. Canquya soils have a mollic epipedon and do not have an argillic horizon. Yarbam soils are formed from calcareous parent material and have a mollic epipedon.
DRAINAGE AND PERMEABILITY: Well drained; moderate to rapid runoff; moderate permeability.
USE AND VEGETATION: Used for recreation and wildlife habitat. Vegetation includes Emory oak, birchleaf mountain mahogany, alligator juniper, agave, nolina, bullgrass, sideoats grama, crinkleawn and wait-a-minute mimosa.
DISTRIBUTION AND EXTENT: Southern Arizona. Tomarizo soils are of limited extent. MLRA is 41.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Cochise County, Arizona; Soil survey of Coronado National Memorial; 1996.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 4 inches (A horizon)
Argillic horizon - The zone from 4 to 12 inches (Bt1, Bt2 horizons)
Lithic contact - The boundary at 12 inches (R horizon)
Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy Tenth Edition, 2006.