LOCATION ANIMAS                  CO+MT WY

Established Series
Rev. RFB/RHM/KLS
09/2022

ANIMAS SERIES

The Animas series consists of somewhat poorly drained soils formed in material weathered from igneous rock deposited over clayey shale. Animas soils are on hummocks. Slopes range from 4 to 65 percent. The mean annual precipitation is about 1,000 to 1,100 mm and the mean annual air temperature is about 3 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive Aquic Argicryolls

TYPICAL PEDON: Animas loam - forest. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 3 cm; undecomposed twigs, needles, bark, and other woody and herbaceous material. (0 to 3 cm thick)

A1--3 to 16 cm; dark grayish brown (10YR 4/2) loam, black (10YR 2/1) moist; strong medium granular structure parting to moderate fine granules; soft, very friable, slightly sticky and slightly plastic; many medium and coarse roots; slightly acid; gradual irregular boundary. (5 to 15 cm thick)

A2--16 to 33 cm; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; common medium distinct yellowish brown (10YR 5/6) mottles; weak medium subangular blocky structure parting to strong medium granules; soft, very friable, slightly sticky and slightly plastic; 5 percent igneous gravel; common fine and medium roots; slightly acid; gradual irregular boundary. (8 to 18 cm thick)

Bt--33 to 61 cm; light brown (7.5YR 6/4) gravelly sandy clay loam, brown (7.5YR 4/4) moist; common fine strong brown (7.5YR 5/6) mottles, moderate coarse subangular blocky structure; very hard, very firm, sticky and plastic; 15 percent igneous gravel; few fine and medium roots; thin patchy clay films; moderately acid; gradual irregular boundary. (18 to 33 cm thick)

C--61 to 100 cm; brown (7.5YR 5/4) gravelly sandy clay loam, brown (7.5YR 4/4) moist; common medium distinct dark brown (7.5YR 3/2), strong brown (7.5YR 5/6), and greenish gray (5GY 5/1) mottles; massive; very hard, very firm, sticky, and plastic; 15 percent gravel, 10 percent stones; few fine roots; moderately acid. (30 to 50 cm thick)

Cr--100 to 130 cm; clay shale.

TYPE LOCATION: Archuleta County, Colorado; Sec. 4, T. 36 N., R. 1 E., NMPM.

RANGE IN CHARACTERISTICS:
Depth to shale--50 to 100 cm
Rock fragment content--0 to 35 percent igneous gravel, throughout

A horizons
Hue--7.5YR or 10YR
Value--3 through 5 dry, 2 or 3 moist
Chroma--1 or 2
Texture--loam or sandy loam

Bt and C horizons
Hue--7.5YR through 5YR
Value--5 through 7 dry, 3 through 6 moist
Chroma--1 through 6
Texture--sandy clay loam or clay loam
Clay content--25 to 35 percent clay

The C horizon has common to many distinct mottles.

COMPETING SERIES: None listed

GEOGRAPHIC SETTING:
Landform--hummocky terrain
Elevation--1975 to 3050 meters
Slope--4 to 65 percent
Parent material--weathered igneous rock deposited over clayey shale
Mean annual precipitation--1000 to 1200 mm
Mean annual air temperature--about 3 degrees C
Mean annual summer temperature--12 degrees C

GEOGRAPHICALLY ASSOCIATED SOILS: None listed

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderately permeable

USE AND VEGETATION: Used mainly for timber production and wildlife habitat. Principal vegetation is Engelmann spruce, white fir, and aspen.

DISTRIBUTION AND EXTENT: Animas soils are of small extent in southwestern Colorado, western Wyoming and western Montana; MLRAs 43B, 46

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Archuleta County (Piedra Area), Colorado, 1974

REMARKS: Converted to metric and O horizons were updated to start at zero. Competing series section was not updated. 2/2022

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National Cooperative Soil Survey
U.S.A.