LOCATION PENITENTE NMEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic Typic Humicryepts
TYPICAL PEDON: Penitente cobbly loam, above timberline. (Colors are for dry soil unless otherwise noted.)
01 & 02--1 inch to 0; organic mat of undecomposed and partially decomposed plant remains of roots and leafy parts of kobresia. (0 to 1 inch thick)
A11---0 to 10 inches; very dark gray (10YR 3/1) cobbly loam, black (10YR 2/1) moist; strong fine granular structure; soft, very friable; many fine roots; many fine and very fine pores; approximately 20 percent cobbles; strongly acid (pH 5.2); clear smooth boundary. (6 to 16 inches thick)
A12--10 to 13 inches; dark brown (7.5YR 3/2) very cobbly loam, very dark brown (7.5YR 2/2) moist; weak fine subangular blocky structure that separates to strong fine granular; soft, very friable; common fine roots; many fine and very fine pores; approximately 40 percent cobbles; strongly acid (pH 5.1); clear smooth boundary. (2 to 4 inches thick)
B2ir--13 to 24 inches; brown (7.5YR 4/4) extremely cobbly sandy loam, brown (7.5YR 3/2) moist; weak medium subangular blocky structure; slightly hard, very friable; common fine roots; many medium pores; approximately 70 percent cobbles and stones; many stones have iron stains of reddish brown (5YR 4/4) moist; very strongly acid (pH 5.0); gradual smooth boundary. (8 to 16 inches thick)
C--24 to 60 inches; brown (7.5YR 5/4) extremely cobbly sandy loam, dark brown (7.5YR 3/2) moist; massive; slightly hard, very friable; approximately 70 percent cobbles and stones; few medium roots; many medium pores; very strongly acid (pH 5.0).
TYPE LOCATION: Santa Fe County, New Mexico; SW1/4 NE1/4 section 10, T.18N., R.11E.
RANGE IN CHARACTERISTICS: Rock fragments range from 40 to 80 percent in the control section. The umbric horizon ranges from 10 to 20 inches thick. The solum ranges from 16 to 26 inches thick. The solum is very strongly acid or strongly acid (pH 4.4 or 5.5). The mean annual soil temperature is less than 32 degrees F.
The A1 horizon has hue of 10YR or 7.5YR, value of 3 or 4 dry, 2 or 3 moist, and chroma of neutral through 2.
The B2ir horizon has hue of 7.5YR or 5YR, value of 4 through 6 dry, 3 through 5 moist, and chroma of 2 through 4. It is typically sandy loam but ranges from 5 to 25 percent, in silt from 10 to 40 percent, and in sand from 40 to 75 percent.
The C horizon has hue of 10YR or 7.5YR. Its texture is similar to that of the B horizon. It is very strongly to medium acid (pH 4.6 to 5.8).
COMPETING SERIES: These are the Bross, Buell, Goodlow, Gramm, Hummington, Meredith, Mirror and Ptarmigan series. Bross soils have an A2 horizon and lack a Bir horizon. Buell, Goodlow, Gramm and Hummington soils have a mean annual soil temperature above 32 degrees F. Meredith soils have fragmental substrata. Mirror and Ptarmigan soils have a lithic contact at depths of less than 40 inches. Ptarmigan soils are nonskeletal.
GEOGRAPHIC SETTING: Penitente soils are on mountain tops above timberline at elevations from 12,000 to 13,000 feet. They formed in material consisting mostly of granite, gneiss and schist. Slopes range from 5 to 60 percent. The mean annual precipitation ranges from 35 to 55 inches. The mean annual air temperature is about 28 to 30 degrees F. The frost free season is 30 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Nambe and Presa soils. Nambe soils lack an umbic epipedon. Presa soils have argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Watershed and wildlife are the chief uses. Kobresia, timberline bluegrass, shrubby cinquefoil, and corex are the chief plants.
DISTRIBUTION AND EXTENT: Above timberline in Northern Mexico. The series is of small extent.
MLRA OFFICE RESPONSIBLE: Lakewood, Colorado
SERIES ESTABLISHED: Santa Fe County (Santa Fe Area), New Mexico, 1970.
ADDITIONAL DATA: Riverside Laboratory S70NM-26-94 and S70NM-26-95.