LOCATION PATOS NMEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, mixed, superactive, mesic Aridic Haplustalfs
TYPICAL PEDON: Patos stony loam--Woodland Savannah.
(Colors are for dry soil unless otherwise noted.)
A--0 to 4 inches; dark brown (7.5YR 4/2) stony loam,
dark brown (7.5YR 3/2) moist; moderate fine granular
structure; soft, very friable, slightly sticky and slightly
plastic; many fine and very fine roots; 20 percent stones;
mildly alkaline (pH 7.6); clear smooth boundary. (3 to 6
inches thick)
Bt1--4 to 7 inches; reddish brown (5YR 4/4) stony clay
loam, reddish brown (5YR 4/3) moist; moderate fine
subangular blocky structure; hard, firm, sticky and plastic;
many fine and very fine roots; few fine clay films on faces
of peds; 20 percent stones; mildly alkaline (pH 7.6); clear
smooth boundary. (0 to 6 inches thick)
Bt2--7 to 30 inches; reddish brown (5YR 4/4) very stony
clay, reddish brown (5YR 4/4) moist; moderate coarse
prismatic structure parting to moderate medium and coarse
subangular blocky; very hard, firm, sticky and plastic;
common fine and coarse roots; many thick clay films on faces
of peds; 15 percent cobbles and 25 percent stones; mildly
alkaline (pH 7.8); clear wavy boundary. (15 to 30 inches
thick)
Bk1--30 to 40 inches; brown (7.5YR 5/4) extremely stony
clay loam, dark brown (7.5YR 4/4) moist; weak medium
subangular blocky structure; very hard, firm, sticky and
plastic; common coarse and few fine roots; 70 percent
stones; violently effervescent; common medium nodules of
calcium carbonate and coatings on undersides of rocks;
moderately alkaline (pH 8.2); clear wavy boundary. (6 to 15
inches thick)
Bk2--40 to 60 inches; pink (7.5YR 8/4) extremely stony
clay loam, pink (7.5YR 7/4); moist; massive; hard, firm,
sticky and plastic; few fine roots; 15 percent cobbles and
55 percent stones; violently effervescent; 15 to 30 percent
calcium carbonate equivalent; horizon engulfed by calcium
carbonate; moderately alkaline (pH 8.4).
TYPE LOCATION: Lincoln County, New Mexico; about 5 miles
west of Encinoso; 200 feet east and 50 feet north of where
road crosses Forest Service boundary in the SW1/4 NW1/4,
sec. 26 T. 7 S., R. 16 E.
RANGE IN CHARACTERISTICS:
Soil Moisture: Intermittently moist in some part of the
moisture control section December through April and July
through October
Soil Temperature: 50 to 54 degrees F.
Depth to calcic horizon: 20 to 40 inches
Rock fragments: 35 to 65 percent cobbles and stones in the particle-size control section
Clay: 35 to 60 percent in the particle-size control section
A horizon: Hue - 7.5YR or 10YR
Value: 3 through 5
Chroma: 2 through 4
Bt horizon: Hue- 5YR or 7.5YR
Value: 4 or 5
Chroma: 2 through 4
Bk horizon: Hue - 5YR or 7.5YR
Value: 4 through 8
Chroma: 1 through 4
Calcium carbonate equivalent: more than 15 percent
COMPETING SERIES: These are the
Cochiti and Divasadero
soils. Cochiti soils have calcic horizon.
Devisadero soils
have bedrock within 40 inches.
GEOGRAPHIC SETTING: Patos soils are on piedmont slopes. Drainageways have cut around the old fans leaving them in a
stable position. Elevation ranges from 5,500 to 7,000 feet.
Most of the slopes range from 1 to 15 percent on the tops of
the fans, but near the base of the mountain and around the
edges of the fans slopes range to 50 percent. The mean
annual precipitation is about 16 to 18 inches, the mean
annual temperature is about 48 to 52 degrees F., and the
frost-free period is about 150 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Plack,
Asparas,
Sampson, and
Purcella soils. Plack soils are on
the older piedmonts and have a petrocalcic horizon.
Purcella soils are in the landscape just below the Patos
soils on old alluvial terraces and have a loamy-skeletal
control section and mollic epipedon. Asparas soils are in
swales and have a mollic epipedon. Sampson soils have a
mollic epipedon and are in the broad swales.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; slow permeability.
USE AND VEGETATION: Patos soils are used for grazing,
wildlife habitat, and wood products. Major species are
western wheatgrass, sideoats grama, blue grama, pinyon pine, alligator juniper, oneseed juniper, wavyleaf oak,
mountainmahogany, and fourwing saltbush.
DISTRIBUTION AND EXTENT: Patos soils are of small extent in southcentral New Mexico.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Lincoln County, New Mexico, 1981.
REMARKS: This changes the classification of this series
from clayey-skeletal, mixed, mesic Typic Haplustalfs to clayey-skeletal, mixed, mesic Aridic Haplustalfs. The
change is due to the current concepts of soil moisture
regimes in New Mexico.
DIAGNOSTIC HORIZONS AND FEATURES RECOGNIZED IN THIS PEDON
ARE:
Ochric epipedon: 0 to 7 inches
Argillic horizon: 7 to 30 inches
Calcic horizon: 30 to 60 inches