LOCATION HILKEN NMEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Ustalfic Petrocalcids
TYPICAL PEDON: Hilken fine sandy loam--on a 1 percent slope in rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; brown (7.5YR 5/4) fine sandy loam, dark reddish brown (5YR 3/4) moist; moderate fine granular structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots; common very fine and fine tubular pores; slightly alkaline; clear smooth boundary. (3 to 7 inches thick)
Bt1--3 to 16 inches; yellowish red (5YR 4/6) sandy clay loam, dark reddish brown (5YR 3/4) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; common very fine and fine tubular pores; common moderately thick clay films on faces of peds and lining pores; slightly alkaline; gradual smooth boundary.
Bt2--16 to 21 inches; yellowish red (5YR 5/6) sandy clay loam, yellowish red (5YR 4/6) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; few very fine and fine tubular pores; common thin clay films on faces of peds and lining pores; moderately alkaline; clear smooth boundary (combined thickness of Bt horizon is 11 to 20 inches thick)
Bk--21 to 27 inches; yellowish red (5YR 5/6) very gravelly sandy clay loam, yellowish red (5YR 4/6) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; few very fine and fine tubular pores; 50 percent angular caliche pebbles; strongly effervescent; moderately alkaline; abrupt wavy boundary. (6 to 13 inches thick)
Bkm--27 to 60 inches; indurated calcium carbonate.
TYPE LOCATION: Guadalupe County, New Mexico; about 10 miles north of Lake Sumner; 550 feet south and 300 feet north of the NE corner of sec. 20, T. 5 N., R. 23 E.
RANGE OF CHARACTERISTICS:
Soil Moisture: Intermittently moist in some part of the soil moisture control section December through March and June through September.
Soil Temperature: 59 to 63 degrees F.
Depth to petrocalcic horizon: 20 to 40 inches
Organic carbon: greater than 0.7 percent throughout the upper 16 inches
Particle-size control section: 18 to 35 percent clay
A horizon - Hue: 5YR or 7.5YR Value: 4 or 5 dry, 3 or 4 moist
Chroma: 3 or 4
Texture: fine sandy loam or loam
Bt horizon - Hue: 5YR or 7.5YR Value: 4 to 6 dry, 3 or 4 moist
Chroma: 4 to 6
Texture: sandy clay loam, loam or clay loam
Bk horizon - Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6
Texture: sandy clay loam, loam or fine sandy loam
Rock fragments: 15 to 60 percent by volume (0 to 5 percent cobbles, 15 to 55 percent pebbles)
COMPETING SERIES: This is the Aymate (NV) series. Similar soils are the are the Douro, Jerag, Palo, Pojo, and Wickett series. Aymate soils are dry in the soil moisture control section for longer periods of time (5 to 8 inches mean annual precipitation). Douro soils have siliceous mineralogy. Jerag and Palo soils have petrocalcic horizons at depths less than 20 inches. Pojo and Wickett soils have less than 18 percent clay in the particle-size control section.
GEOGRAPHIC SETTING: Hilken soils are on mesas and plains. They formed in eolian and alluvium derived dominantly from sandstone and shale. Slopes ranges from 0 to 2 percent. Mean annual temperature ranges from 58 to 60 degrees F. and mean annual precipitation ranges from 12 to 14 inches, of which more than one-half occurs as severe thunderstorms in July through September. The average frost-free period ranges from 180 to 200 days and elevation ranges from 4,200 to 5,300 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Palo series and the Berwolf, Kolar, Neso and Redona soils. The Berwolf and Redona soils are deep and occur in swale positions. Kolar and Neso soils are shallow to petrocalcic horizons and occur on convex ridges.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is negligible on slopes less than 1 percent and very low on 1 to 3 percent slopes.
USE AND VEGETATION: This soil is used for livestock grazing and wildlife habitat. Native vegetation is sideoats grama, blue grama, little bluestem, New Mexico feathergrass, wolftail and black grama.
DISTRIBUTION AND EXTENT: Eastcentral New Mexico. Hilken soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Guadalupe County, New Mexico, 1988.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 3 inches. (A horizon)
Argillic horizon: 3 to 21 inches. (Bt horizons)
Petrocalcic horizon: occurs at a depth of about 27 inches. (Bkm horizon)