LOCATION ALAMA NMEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Ustic Haplocambids
TYPICAL PEDON: Alama silt loam - rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 8 cm (0 to 3 in); reddish brown (5YR 5/4) silt loam, dark reddish brown (5YR 3/4) moist; thin platy structure in the upper 0.5 inch, over moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine roots; many very fine and fine pores; common clusters of fine rounded worm casts; slightly effervescent; moderately alkaline; clear smooth boundary. (5 to 20 cm thick)
Bw1--8 to 20 cm (3 to 8 in); reddish brown (5YR 5/4) silty clay loam, dark reddish brown (5YR 3/4) moist; moderate fine subangular blocky and weak coarse prismatic structure; hard, friable, slightly sticky and slightly plastic; many fine roots; many very fine and fine pores; common clusters of fine rounded worm casts; slightly effervescent; slightly alkaline; clear smooth boundary.
Bw2--20 to 46 cm (8 to 18 in); reddish brown (5YR 5/4) silty clay loam, dark reddish brown (5YR 3/4) moist; moderate fine and medium subangular blocky and weak coarse prismatic structure; hard, friable, slightly sticky and plastic; many fine roots; many fine and very fine pores; few clusters of fine rounded worm casts; strongly effervescent; slightly alkaline; gradual smooth boundary.
Bw3--46 to 71 cm (18 to 28 in); reddish brown (5YR 5/4) silt loam, reddish brown (5YR 4/4) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and plastic; common fine roots; common very fine and few fine pores; few clusters of fine rounded worm casts; strongly effervescent; slightly alkaline; gradual smooth boundary. (combined thickness of the Bw horizon is 50 to 175 cm)
Bk1--71 to 102 cm (28 to 40 in); reddish yellow (5YR 6/6) silt loam, yellowish red (5YR 4/6) moist; weak coarse subangular blocky structure; hard, friable, slightly sticky and plastic; few fine roots; common very fine and fine pores; violently effervescent; calcium carbonate segregated in few fine masses and in seams; moderately alkaline; gradual wavy boundary. (0 to 40 cm thick)
2Bk2--102 to 203 cm (40 to 80 in); reddish yellow (5YR 6/6) loam, yellowish red (5YR 4/6) moist; weak coarse subangular blocky structure; slightly hard, very friable, slightly sticky and plastic; few very fine and fine pores; 2 percent fragments of weathered siltstone; strongly effervescent; calcium carbonate segregated in few fine concretions; moderately alkaline.
TYPE LOCATION: Guadalupe County, New Mexico; about 25 miles east of Santa Rosa; 200 feet north and 2,550 feet west of the southeast corner, sec. 15, T. 8 N., R. 26 E.; Latitude: 34 degrees, 54 minutes, 30 seconds W.; Longitude: 104 degrees, 09 minutes, 55 seconds N.
RANGE IN CHARACTERISTICS:
Soil Moisture: An aridic moisture regime bordering on ustic. The soil moisture control section is dry in all parts for 205 but less than 270 days, cumulative in normal years. October through May are the driest months. These soils are intermittently moist from December through March and June through September.
Mean annual soil temperature: 15 to 18 degrees C (59 to 64 degrees F).
Particle-size control section: 18 to 35 percent clay, less than 15 percent fine sand or coarser.
Coarse fragments: less then 15 percent
Depth to secondary carbonates: 25 to 51 cm (10 to 20 in)
Solum thickness: 152 to 203 cm (60 to 80 in)
A horizon:
Hue: 2.5YR to 7.5YR
Value: 3 to 6, 3 or 4 moist
Chroma: 4 to 6.
Texture: silt loam or loam
Effervescence: none to slight
Reaction: slightly alkaline or moderately alkaline
Bw horizon:
Hue: 2.5YR to 7.5YR
Value: 3 to 7, 3 to 6 moist
Chroma: 3 to 6.
Texture: silt loam, loam, silty clay loam, clay loam
Effervescence: strong to violent
Secondary carbonates: finely disseminated
Reaction: slightly alkaline or moderately alkaline
Bk horizon:
Hue: 2.5YR to 7.5YR
Value: 3 to 7, 3 to 6 moist
Chroma: 3 to 6.
Texture: silt loam, loam, clay loam
Effervescence: violent
Secondary carbonates: 5 to 15 percent finely disseminated, threads, and masses
Reaction: moderately alkaline
2Bk horizon (where present):
Hue: 2.5YR to 7.5YR
Value: 3 to 7, 3 to 6 moist
Chroma: 3 to 6.
Texture: silt loam, loam, clay loam
Effervescence: strong to violent
Secondary carbonates: 5 to 15 percent finely disseminated, threads, masses, and concretions
Coarse fragments: 2 to 10 percent weathered fragments of sandstone or siltstone
Reaction: slightly alkaline or moderately alkaline
BCk or C horizons (below 150 cm where present):
Hue: 2.5YR to 7.5YR
Value: 4 to 7, 4 to 6 moist
Chroma: 3 to 6
Texture: loam, silt loam, clay loam
Effervescence: strong to violent
Secondary carbonates: 5 to 15 percent finely disseminated
Coarse fragments: 2 to 15 percent weathered (rounded prismoidal) fragments of sandstone or siltstone
Reaction: moderately alkaline
COMPETING SERIES: These are the
Hodgins and
Reyab series.
Hodgins soils: have more than 15 percent calcium carbonate equivalent in the control section.
Reyab soils: have solum thickness of less than 100 cm and do not have segregated calcium carbonate in the lower horizons.
GEOGRAPHIC SETTING:
Parent Material: alluvium derived principally from redbed formations of Jurassic, Triassic, Permian, and Pennsylvanian Age
Landform: alluvial fans and piedmont slopes and rarely on low terraces
Slopes: 0 to 5 percent
Mean annual temperature: 15 to 19 degrees C (59 to 66 degrees F).
Mean annual Precipitation: 305 to 381 mm (12 to 15 in).
Precipitation pattern: Mostly summer thundershowers of short duration
Frost-free period: 180 to 215 days
Elevation: 1,040 to 1,680 meters (3,400 to 5,500 ft).
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Hassell,
Los Tanos,
Montoya, and
Tucumcari soils.
Hassell soils: more than 15 percent fine sand or coarser in the particle-size control section and are on slightly higher positions on pediments and truncated pediments below escarpments.
Los Tanos soils: less than 18 percent clay in the particle-size control section, have sandstone bedrock at depths of 50 to 100 cm, and are on slightly higher positions on low hills ridges, and mesas.
Montoya soils: more then 35 percent clay in the particle-size control section and have cracks more than 1 cm. wide when dry and are on lower positions on channeled flood plains, low terraces, and alluvial fans.
Tucumcari soils: have more than 15 percent fine sand or coarser in the particle-size control section and are on slightly lower positions on alluvial fans and valley slopes.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately slow. Runoff is negligible on slopes less than 1 percent, very low on 1 to 3 percent slopes, and low on 3 to 5 percent slopes.
USE AND VEGETATION: Principal use is livestock grazing, but where irrigation water is available, some areas are used for growing grain sorghums, alfalfa, and cotton. Present native vegetation is principally blue grama, black grama, galleta, tobosa, and alkali sacaton. The ecological site is Loamy (R070XB052NM).
DISTRIBUTION AND EXTENT: Upper Pecos River Valley (MLRA 70B in LRR G) of east-central New Mexico. This series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Southwest Quay Area, New Mexico, 1958.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 8 cm. (A horizon)
Cambic horizon 8 to 71 cm. (Bw horizon)
ADDITIONAL DATA: none
TAXONOMIC VERSION: Keys to Soil Taxonomy, Tenth Edition, 2006