Established Series


The Eckert series consists of soils that are shallow to indurated limestone bedrock. These well drained soils formed in residuum derived from limestone of Ordovician and Cambrian age. These nearly level to moderately steep soils are on summits, shoulders, and backslopes of ridges on dissected plateaus. Slope ranges from 1 to 20 percent slopes. Mean annual air temperature is about 19 degrees C (66 degrees F), and the mean annual precipitation is about 668 mm (26 in).

TAXONOMIC CLASS: Loamy-skeletal, mixed, active, thermic Lithic Haplustolls

TYPICAL PEDON: Eckert very stony silt loam--rangeland. (Colors are for dry soil unless otherwise stated.)

A--0 to 30 cm (0 to 12 in); brown (7.5YR 4/3) very stony silt loam, dark brown (7.5YR 3/2) moist; weak fine subangular blocky and granular structure; hard, friable; many very fine and fine roots; 8 percent limestone gravel, 25 percent cobbles, and 15 percent stones; slightly effervescent; moderately alkaline; abrupt wavy boundary. (Thickness of the A horizon is 10 to 35 cm [4 to 14 in])

R--30 to 55 cm (12 to 22 in); gray (10YR 6/1) indurated limestone bedrock; fractured; contains less than 5 percent fine-earth in fractures and crevices.

TYPE LOCATION: Gillespie County, Texas; From the intersection of Ranch Road 648 and Ranch Road 783 in Doss, approximately 3.6 miles north on Ranch Road 783 (700 feet south of the Mason County line), 0.5 mile southeast and northeast on a private road, and 10 feet west in rangeland. (Cherry Springs USGS topographic quadrangle; Latitude: 30 degrees, 29 minutes, 42 seconds N; Longitude: 99 degrees, 7 minutes, 29 seconds W; NAD83)

Solum thickness: 10 to 35 cm (4 to 14 in)
Effervescence: Noneffervescent to strongly
Reaction: Neutral to moderately alkaline

Particle-size control section (weighted average):
Clay content: 15 to 35 percent
Rock fragments: Amount-35 to 70 percent by volume, size-2 to 600 mm, kind-limestone

A horizon
Hue: 7.5YR or 10YR
Value: 3 or 4
Chroma: 2 or 3
Texture: Fine sandy loam, very fine sandy loam, silt loam, loam, or clay loam, and their very or extremely, gravelly, cobbly or stony phases

R layer
Horizon thickness: Greater than 25 cm (10 in)
Cementation: Strongly cemented or indurated
Kind: Crystalline dolomitic limestone bedrock, containing appreciable amounts of glauconite

Rayford (OK) is in the same family. Similar series are Kiti (OK), Palopinto (TX), Timhill (OK), and Woodford (OK).
Kiti soils: Are formed in material weathered from tilted limestone of Ordovician and pre-Cambrian age.
Palopinto soils: Are formed in material weathered from limestone bedrock of Pennsylvanian age.
Rayford soils: Are formed in material weathered from limestone conglomerate of Pennsylvanian age and the mean annual soil temperature is cooler.
Timhill soils: Are formed in material weathered from tilted rhyolite of Cambrian age.
Woodford soils: Are formed in material weathered from sandstone of Mississippian age.

Parent material: Hard crystalline dolomitic limestone, containing appreciable amounts of glauconite of Cambrian age.
Landscape: Dissected plateaus
Landform: Summits, shoulders, and backslopes of ridges
Slope: 1 to 20 percent
Climate: Dry subhumid
Soil moisture: 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: 18 to 19 degrees C (64 to 66 degrees F)
Mean annual precipitation: 610 to 762 mm (24 to 30 in)
Frost-free period: 210-240 days
Elevation: 305 to 671 m (1000 to 2200 ft)
Thornthwaite annual P-E indices: 38 to 44

These are the Eckrant (TX), Nebgen (TX), Oben (TX), Tarrant (TX+OK), Pedernales (TX), and Yates (TX) series.
Eckrant, Tarrant and Yates soils: Occur on similar landform positions and formed in limestone.
Nebgen and Oben soils: Occur on similar landscapes and formed in sandstone.
Pedernales soils: Occur on footslopes of alluvial plains and/or alluvial plain remnants.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is very low on 1 to 3 percent slopes, low on 3 to 5 percent slopes, and medium on 5 to 15 percent slopes, high on 15 to 20 percent slopes.

USE AND VEGETATION: Used for rangeland. The climax plant community is grassland with an occasional live oak and low shrubs throughout the landscape. Mid and short grasses along with forbs and a few small shrubs are present. The dominant grass is little bluestem. Other grasses include green sprangletop, sideoats grama, Arizona cottontop, vine mesquite, pinhole bluestem, fall witchgrass, and hooded windmillgrass. Woody plants include live oak, tasajillo, Texas persimmon, yucca, and mesquite. Forbs, such as sagewort, and gaura are present. With heavy stocking rates the site could potentially deteriorate to a plant community of croton, pricklypear, tasajillo, Texas persimmon, mesquite, and other woody plants.

DISTRIBUTION AND EXTENT: Central Texas. Southwest Plateaus and Plains Range and Cotton Region, LLR I: MLRA 81B-Edwards Plateau, Central Part; MLRA 81C-Edwards Plataeu, Eastern Part; and MLRA 82A-Texas Central Basin. This series is of moderate extent.


SERIES ESTABLISHED: Gillespie County, Texas; 1970.

REMARKS: Eckert soils were previously included with the Yates series.

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 0 to 30 cm (0 to 12 in) (A horizon)
Lithic contact: at 30 cm (12 in) (top of the R layer)


TAXONOMIC VERSION: Keys to Soil Taxonomy, 11th Edition, 2010.

National Cooperative Soil Survey