LOCATION PENISTAJA NM+AZEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Ustic Haplargids
TYPICAL PEDON: Penistaja fine sandy loam-rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 2 inches; brown (7.5YR 4/4) fine sandy loam, dark brown (7.5YR 3/4) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine irregular pores; neutral; abrupt smooth boundary. (2 to 8 inches thick)
Bt1--2 to 6 inches; brown (7.5YR 5/4) sandy clay loam, brown (7.5YR 4/4) moist; weak medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots; common very fine tubular pores; few thin clay films lining pores; neutral; abrupt smooth boundary. (2 to 10 inches thick)
Bt2--6 to 16 inches; strong brown (7.5YR 4/6) sandy clay loam, brown (7.5YR 4/4) moist; strong medium subangular blocky structure; slightly hard, friable, slightly sticky, nonplastic; common very fine and fine roots; common very fine tubular pores; many moderately thick clay films on faces of peds and lining pores; slightly alkaline; clear smooth boundary. (5 to 13 inches thick)
Bt3--16 to 22 inches; strong brown (7.5YR 5/6) sandy clay loam, strong brown (7.5YR 4/6) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; common very fine and fine roots common very fine tubular pores; common moderately thick clay films on faces of peds and lining pores; slightly alkaline; abrupt smooth boundary. (0 to 8 inches thick)
Bk--22 to 53 inches; light brown (7.5YR 6/4) sandy loam, strong brown (7.5YR 5/6) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; common very fine irregular pores; violently effervescent; calcium carbonate segregated as common medium rounded soft masses; moderately alkaline; clear smooth boundary. (10 to 42 inches thick)
C--53 to 70 inches; reddish yellow (7.5YR 6/6) sandy loam, strong brown (7.5YR 5/6) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine irregular pores; strongly effervescent; moderately alkaline.
TYPE LOCATION: Cibola County, New Mexico; Bluewater Quadrangle; about 2.25 miles north of Anaconda Mill; 400 feet west and 2,000 feet north of the southeast corner of Section 6, T. 12 N., R. 10 W. 107 degrees, 55 minutes, 36 seconds west longitude; 35 degrees, 17 minutes, 46 seconds north latitude.
RANGE IN CHARACTERISTICS:
Soil Moisture: Intermittently moist in some part of the soil moisture control section during December to March and July to September. The soil is driest during May and June. Ustic aridic soil moisture regime.
Soil Temperature: 51 to 59 degrees F.
Organic matter: averages more than 1 percent organic matter in the upper 16 inches
Depth to base of argillic horizon: 13 to 35 inches
Reaction: Neutral to moderately alkaline
A horizon
Hue: 5YR, 7.5YR, 10YR
Value: 4 through 6 dry, 3 through 5 moist
Chroma: 2 through 6, dry or moist
Texture: loamy fine sand, sandy loam, fine sandy loam, loam
Rock fragments: less than 15 percent
Effervescence: noneffervescent
Bt horizon
Hue: 5YR, 7.5YR
Value: 4 through 6 dry, 3 through 5 moist
Chroma: 3 through 6, dry or moist
Texture: sandy clay loam, clay loam; a weighted average of 20 to 35 percent clay and 40 to 80 percent sand with more than 35 percent fine sand or coarser
Rock fragments: less than 10 percent
Effervescence: noneffervescent
Bk and C horizons
Hue: 5YR, 7.5YR, 10YR
Value: 4 through 8 dry, 3 through 7 moist
Chroma: 3 through 6, dry or moist
Texture: sandy loam, fine sandy loam, loam, sandy clay loam
Rock fragments: less than 10 percent
Calcium carbonate equivalent: less than 15 percent
Effervescence: strongly or violently
COMPETING SERIES: These are the Balon (AZ), Blancot (NM), Bowbac (WY), Buckle (NM), Cambria (WY), Cerropelon (NM), Chilerojo (NM), Chilojo (NM), Cumacho (NM), Cushman (WY), Decolney (WY), Doakum (NM), Forkwood (WY), Fort (CO), Gaddes (AZ), Gapbutte (AZ), Gapmesa (CO), Hagerman (NM), Hagerwest (NM), Hiland (WY), Mentmore (NM), Oelop (NM), Olney (CO), Palacid (NM), Pokeman (WY), Potts (WY), Pugsley (WY), Quagwa (AZ), Redpen (NM), Spangler (WY), Sundance (CO), Tamarindo (NM), Teckla (WY) and Yenlo (CO) series. Balon soils are noneffervescent throughout. Blancot and Yenlo soils have hue of 10YR and 2.5Y. Bowbac, Cambria, Cushman, Delconey, Forkwood, Hiland, Pokeman, Potts, Pugsley, Spangler and Teckla soils are moist in May and June. Buckle, Oelop and Palacid soils contain less than 40 percent sand. Doakum soils average less than 1 percent organic matter in the upper 16 inches. Quagwa soils contain less than 25 percent sand. Cerropelon, Cumacho, Gaddes, Gapbutte, Gapmesa, Hagerman, and Hagerwest soils have bedrock at moderate depths. Chilerojo, Fort, Olney, Sundance and Tamarindo soils attempt to reflect the effects of soil forming agents unique to the Great Plains. Redpen soils have 2.5YR hue. Mentmore soils have 2.5Y hue. Chilojo soils are inactive.
GEOGRAPHIC SETTING: Penistaja soils are on mesas, plateaus, hills, cuestas and bajadas. Slopes are 0 to 10 percent. They formed in alluvium, fan alluvium, slope alluvium and eolian material derived principally from sandstone and shale. Elevations range from 4,800 to 7,100 feet. The mean annual precipitation is 10 to 14 inches. Mean annual air temperature is 49 to 57 degrees F. The frost-free period is 115 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bond, Hagerman and Querencia soils. Querencia soils do not have argillic horizons. Bond soils have a lithic contact at less than 20 inches. Hagerman soils have a lithic contact at 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; low runoff; moderate permeability.
USE AND VEGETATION: Penistaja soils are used for livestock grazing. Vegetation is blue grama, western wheatgrass, Indian ricegrass, galleta, winterfat and fourwing saltbush.
DISTRIBUTION AND EXTENT: Northwestern New Mexico and northeastern Arizona. MLRA 35 and 36, LRR-D. This series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Santa Fe County (Santa Fe Area), New Mexico, 1970.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 2 inches (A horizon)
Argillic horizons: The zone from 2 to 22 inches (Bt horizons)
The type location of the Penistaja series was moved from Sandoval County to Cibola County in 1983 to better reflect the present concept of the Penistaja series.
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006
The Penistaja and Doakum series were originally classified in Ustollic and Ustalfic subgroups, respectively. A later revision to Soil Taxonomy combined these into one Ustic subgroup resulting in duplication of series differentia and inconsistent field mapping. Surface organic matter content has been better defined as differentia but the Doakum series may need to be inactivated if concept confusion persists after 7/2007