LOCATION ACOVE TX
Established Series
Rev. ALN-ACT-JAM
04/2011
ACOVE SERIES
The Acove series consists of soils that are moderately deep to paralithic sandstone bedrock. These well drained soils formed in loamy residuum derived from sandstone of Cambrian age. These nearly level to strongly sloping soils are on shoulders and summits of ridges on dissected plateaus of the Central Basin. Slope ranges from 0 to 12 percent. Mean annual air temperature is about 19 degrees C (67 degrees F), and mean annual precipitation is about 686 mm (27 in).
TAXONOMIC CLASS: Fine, mixed, active, thermic Typic Haplustalfs
TYPICAL PEDON: Acove loamy sand, in rangeland. (Colors are for dry soil unless otherwise stated.)
A1--0 to 23 cm (0 to 9 in); brown (7.5YR 4/2) loamy sand, dark brown (7.5YR 3/2) moist; weak coarse granular structure; hard, very friable; many fine roots; many fine pores; few fine rounded quartz gravel; few fine angular sandstone gravel; strongly acid; gradual smooth boundary.
A2--23 to 38 cm (9 to 15 in); brown (7.5YR 4/2) loamy sand, dark brown (7.5YR 3/2) moist; weak, coarse granular structure; hard, very friable; many fine roots; many fine pores; few fine rounded quartz gravel; common fine and medium angular sandstone gravel; slightly acid; clear wavy boundary. (Combined thickness of the A horizon is 17 to 48 cm [7 to 19 in])
Bt1--38 to 48 cm (15 to 19 in); yellowish brown (10YR 5/4) very flaggy sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate fine subangular blocky structure; very hard, friable, sticky and slightly plastic; many fine roots; common distinct clay films on all faces of peds and on rock fragments; 59 percent strongly cemented iron-enriched sandstone flagstone fragments; black pendants having reddish brown interiors on the lower sides of sandstone fragments; slightly acid; clear wavy boundary.
Bt2--48 to 64 cm (19 to 25 in); reddish yellow (7.5YR 6/6) flaggy clay, strong brown (7.5YR 5/6) moist; moderate fine angular blocky structure; very hard, firm, sticky and plastic; common fine roots; common fine pores; common distinct clay films on all faces of peds; 30 percent strongly cemented reddish brown platy ironstone flagstone fragments, 12 to 50 mm (0.5 to 2 in) thick and up to 350 mm (14 in) across that is discontinuous, wavy and occurs mainly in upper part of horizon; slightly acid; clear wavy boundary.
Bt3--64 to 97 cm (25 to 38 in); brownish yellow (10YR 6/6) clay, yellowish brown (10YR 5/6) moist; moderate medium angular blocky structure; very hard, very firm, sticky and plastic; few fine roots; few fine pores; common distinct clay films on all faces of pedons and on rock fragments; 10 percent red (2.5YR 4/6) sandstone fragments 25 to 200 mm (1 to 8 in) across the long axis; dark brown to black stains on lower face of sandstone; few to common weakly cemented black and brown concretions 6 to 13 mm (0.25 to 0.5 in) in diameter; slightly acid; abrupt wavy boundary. (Combined thickness of the Bt horizon is 28 to 81 cm [11 to 32 in])
Cr--97 to 163 cm (38 to 64 in); red (10R 4/6) weakly cemented, but consolidated sandstone, red (2.5YR 4/6) dry; few yellow (10YR 7/6) strongly cemented sandstone plates up to 19 mm (0.75 in) thick; clay in horizontal cracks up to 5 cm (2 in) thick; few very fine roots in cracks in upper 15 cm (6 in); slightly acid.
TYPE LOCATION: McCulloch County, Texas; From the intersection of Texas Highway 71 and Ranch Road 1851 in McCulloch County, Texas; south of the town of Voca; 0.3 mile east on Texas Highway 71, and 100 feet north in rangeland. Voca USGS topographic quadrangle; Latitude: 31 degrees 0 minutes 11.09 seconds N; Longitude: 99 degrees 10 minutes 52.44 seconds W, NAD83.
RANGE IN CHARACTERISTICS:
Depth to paralithic contact: 61 to 100 cm (24 to 40 in)
Solum thickness: 61 to 100 cm (24 to 40 in)
Particle-size control section (weighted average):
Clay content: 35 to 45 percent
Coarse fragments: 15 to 35 percent
A horizon
Hue: 7.5YR or 10YR
Value: 4 or 5
Chroma: 2 to 4
Texture: Loamy sand, loamy fine sand, sandy loam, or fine sandy loam; and/or gravelly to flaggy or very gravelly to very flaggy phases
Clay content: 5 to 17 percent
Coarse fragments: Amount-5 to 60 percent by volume; size-gravel to flagstone
Other features: In pedons where moist value and chroma are 3 or less, the epipedon is not thick enough for a mollic epipedon.
Reaction: Strongly acid to neutral
Bt1 horizon
Hue: 5YR to 10YR
Value: 4 to 6
Chroma: 4 to 8
Texture: Fine sandy loam or sandy clay loam; and/or their gravelly to flaggy or very gravelly to very flaggy phases
Clay content: 12 to 35 percent
Coarse fragments: Amount-0 to 60 percent by volume, in the form of a stone line, range from less than 30 to 610 mm (0.5 to 24 in) across, predominately 251 to 610 mm (10 to 24 in)
Reaction: Slightly acid to neutral
Bt2 horizon
Hue: 5YR to 2.5Y
Value: 4 to 6
Chroma: 4 to 8
Texture: Sandy clay or clay, and/or their channery, flaggy, very channery or very flaggy phases
Coarse fragments: Amount-5 to 60 percent by volume, from less than 30 to 610 mm (0.5 to 24 in) across, predominately 251 to 610 mm (10 to 24 in) across
Clay content: 35 to 55 percent
Reaction: slightly acid to neutral
Cr layer
Hue: 10R to 5YR
Cementation: weakly cemented to moderately cemented
Other features: clay in horizontal cracks up to 5 cm (2 in) thick
R layer (where present is interbedded with the Cr layer)
Cementation: strongly to indurated sandstone bedrock
COMPETING SERIES:
These are the
Bluegrove (TX),
Callahan (TX), and
Lindale (TX) series.
Bluegrove soils: do not have a stone line in the upper argillic horizons and soil temperature is cooler.
Callahan and
Lindale soils: do not have a stone line in the upper argillic horizons, and have identifiable secondary carbonates within 76 cm (30 in) of the soil surface.
GEOGRAPHIC SETTING:
Parent material: Loamy residuum derived from sandstone of Cambrian age, primarily the Hickory formation.
Landscape: Dissected plateaus of the Central Basin
Landform: shoulders and summits of ridges
Slope: 0 to 12 percent, dominantly 1 to 8 percent
Climate: Dry subhumid
Soil moisture: A typic ustic moisture regime.
Precipitation Pattern: The majority of the yearly amount occurs during the fall and spring months. The winter and summer months are normally drier.
Mean annual air temperature: 17.8 to 18.9 degrees C (64 to 66 degrees F)
Mean annual precipitation: 610 to 762 mm (24 to 30 in)
Frost-free period: 207 to 262 days
Elevation: 366 to 610 m (1,200 to 2,000 ft)
Thornthwaite P-E index: 38 to 44
GEOGRAPHICALLY ASSOCIATED SOILS: These include the
Cobb (TX),
Demona (TX),
Katemcy (TX),
Pedernales (TX), and
Pontotoc (TX) series.
Cobb soils: occur on similar positions
Demona soils: have sandy epipedons thicker than 50 cm (20 in), have gray mottles in the argillic horizons, and occur in lower positions in the landscape.
Katemcy soils: occur on similar positions and formed over schist.
Pedernales and
Pontotoc soils: occur on lower positions; in addition, Pedernales soils are very deep and have abrupt textural changes from the surface to the argillic horizons.
Pontotoc soils: are very deep, and have coarse-loamy particle size control sections and have hues of 2.5YR or redder in the argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is very low on 1 to 3 percent slopes, and low on 3 to 5 percent slopes.
USE AND VEGETATION: Used mostly for rangeland. Some areas are used for growing peanuts, small grains, and grain sorghums. Native vegetation is sideoats grama, fall witchgrass, threeawn, sand dropseed, and little bluestem. Scattered trees include post oak, mesquite, prickly ash, and hackberry.
DISTRIBUTION AND EXTENT: Southwest Plateaus and Plains Range and Cotton Region, LRR-I. MLRA 82A-Texas Central Basin. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: McCulloch County, Texas; 1970.
REMARKS:
The surface texture in the typical pedon was fine sandy loam and was changed based on National Soil Survey Laboratory data at the type location.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 38 cm (0 to 15 in) (A1 and A1 horizons)
Argillic horizon: 38 to 97 cm (15 to 38 in) (Bt horizons)
Stone line feature: 38 to 48 cm (15 to 19 in) (Bt1 horizon)
Paralithic contact: soft, weathered sandstone bedrock at 97 cm (38 in) (top of Cr layer)
ADDITIONAL DATA: National Soil Survey Laboratory data from McCulloch County, TX near the series type location (Pedon S09TX307002 and Lab numbers 09N02904-09N02909.)
TAXONOMIC VERSION: Keys to Soil Taxonomy, 11th Edition, 2010.
National Cooperative Soil Survey
U.S.A.