LOCATION LUCKENBACH              TX

Established Series
Rev. CLN-ELG-ACT-ALB
04/2011

LUCKENBACH SERIES

The Luckenbach series consists of very deep, well drained, moderately slowly permeable soils that formed in ancient loamy or clayey alluvium. These nearly level and gently sloping soils are on alluvial plain remnants or stream terraces and along narrow valleys on dissected plateaus. Slope ranges from 0 to 5 percent. Mean annual precipitation is about 660 ,mm (26 in) and mean annual temperature is about 18 degrees C (65 degrees F).

TAXONOMIC CLASS: Fine, mixed, superactive, thermic Typic Argiustolls

TYPICAL PEDON: Luckenbach clay loam--in cropland. (Colors are for dry soil unless otherwise stated.)

Ap--0 to 20 cm (0 to 8 in); very dark grayish brown (10YR 3/2) clay loam, very dark brown (10YR 2/2) moist; moderate fine subangular blocky structure; slightly hard, firm, slightly sticky and plastic; common fine and medium roots; noneffervescent; slightly alkaline; abrupt smooth boundary.

A--20 to 46 cm (8 to 18 in); brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and plastic; few fine roots; noneffervescent; slightly alkaline; clear smooth boundary. (Combined thickness of the A horizon is 25 to 51 cm [10 to 20 in])

Bt--46 to 76 cm (18 to 30 in); reddish brown (5YR 5/4) clay, reddish brown (5YR 4/4) moist; moderate fine blocky and subangular blocky structure; hard, firm; few fine roots; 5 percent clay films; few fine calcium carbonate concretions; very slightly effervescent; moderately alkaline; gradual smooth boundary. (Thickness of the Bt horizon is 25 to 51 cm [10 to 22 in])

Btk--76 to 97 cm (30 to 38 in); brown (7.5YR 5/4) clay, brown (7.5YR 4/4) moist; moderate fine subangular blocky and blocky structure; hard, firm; few fine roots; 5 percent by volume calcium carbonate concretions; violently effervescent; moderately alkaline; clear smooth boundary. (Thickness of the Btk horizon is 20 to 46 cm [8 to 18 in])

Bk1--97 to 114 cm (38 to 45 in); very pale brown (10YR 7/4) clay loam, light yellowish brown (10YR 6/4) moist; weak fine subangular blocky structure; hard, friable; few fine roots; 10 percent by volume calcium carbonate concretions; few limestone fragments; violently effervescent; moderately alkaline; clear smooth boundary. (Combined thickness of the Bk horizons is 13 to 56 cm [5 to 22 in])

Bk2--114 to 203 cm (45 to 80 in); very pale brown (10YR 7/3) clay loam; weak fine subangular blocky structure; hard, friable; few fine roots; 10 percent concretions and masses of calcium carbonate; 10 percent limestone gravel; violently effervescent; moderately alkaline.

TYPE LOCATION: Gillespie County, Texas; From the intersection of U.S. Highway 290 and Texas Highway 16 in Fredericksburg, 9.1 miles southwest on Texas Highway 16, 3.7 miles west on Morris Ranch Road, and 200 feet south in cultivated field. (Morris Ranch USGS topographic quadrangle; Latitude: 30 degrees, 13 minutes, 22.8 seconds N; Longitude: 99 degrees, 2 minutes, 2.4 seconds W; NAD83)

RANGE IN CHARACTERISTICS:
Soil moisture: Typic ustic moisture regime
Solum thickness: 150 to 200 cm (60 to 80 in)
Mollic epipedon: 30 to 50 cm (12 to 20 in)
Depth to identifiable secondary carbonates: 46 to 71 cm (18 to 28 in)
Particle-size control section (weighted average):
Clay content: 35 to 55 percent
Fragments: 0 to 15 percent by volume

A horizon
Hue: 7.5YR or 10YR
Value: 3 or 4
Chroma: 2 or 3
Texture: Loam, sandy clay loam, or clay loam
Fragments: amount-0 to 5 percent by volume; kind-siliceous; size-fine and medium gravel
Effervescence: None or slightly
Reaction: Slightly acid to slightly alkaline

Bt horizon
Hue: 5YR to 10YR
Value: 4 or 5
Chroma: 2 to 4
Texture: clay loam, sandy clay, or clay
Clay content: 35 to 55 percent
Fragments: amount-0 to 15 percent by volume; kind-siliceous; size-fine and medium gravel
Identifiable calcium carbonate: amount-0 to 10 percent by volume, kind-concretions and masses
Effervescence: None or slightly
Reaction: Neutral to moderately alkaline

Bk or Btk horizons
Hue: 5YR to 2.5Y
Value: 4 to 6
Chroma: 3 to 6
Texture: Loam, sandy clay loam, clay loam, or clay; and their gravelly phases
Fragments: amount-0 to 20 percent by volume; kind-limestone and siliceous; size-fine and medium gravel
Identifiable calcium carbonate: amount-2 to 10 percent by volume, kind-concretions and masses
Effervescence: Strongly or violently
Reaction: Slightly alkaline or moderately alkaline

COMPETING SERIES: These are the Frankirk (TX), La Casa (OK), Lawton (OK), Pyron (TX), Rowden (TX), Sagerton (TX), and Swenson (TX) series. Similar soils are the Abilene (TX), Anocon (TX), Bexar (TX), and Blanket (TX) series.
Abilene and Blanket soils: Have mollic epipedons more than 51 cm (20 in) thick.
Anocon soils: Have secondary carbonates at depths greater than 71 cm (28 in) and have formed in colluvium and residuum from sandstone and shale.
Bexar, Rowden, and Swenson soils: Are 50 to 100 cm (20 to 40 in) deep to bedrock.
Frankirk soils: Have 2.5YR hue in the argillic horizon and cooler soil temperatures.
Lawton soils: Do not have carbonates within a depth of 122 cm (48 in).
La Casa, Pyron, and Sagerton soils: Have calcic horizons.

GEOGRAPHIC SETTING:
Parent material: The soils formed in thick beds of calcareous clay loams and clays.
Landscape: Alluvial plain remnant
Landform: Footslopes of valleys
Slope: 0 to 5 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 precipitation: 660 to 864 .mm (26 to 34 in)
Mean annual temperature: 18 to 20 degrees C (64 to 68 degrees F)
Frost-free period: 215 to 235 days
Elevation: 152 to 663 m (500 to 2,175 ft)
Thornthwaite annual P-E indices: 36 to 46

GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Blanket, Heaton, Hensley, Krum, Pedernales, and Sunev series.
Blanket soils: Are on similar or slightly lower positions.
Heaton, Hensley, and Pedernales soils: Do not have mollic epipedons. Heaton and Hensley soils are typically on stream divides, low ridges, or nearby slopes.
Pedernales soils: Are on similar positions.
Krum soils: Have clayey surfaces, do not have argillic horizons, and are on similar positions.
Sunev soils: Have a calcic horizon, loamy subsoils, and are on footslopes.

DRAINAGE AND PERMEABILITY: This soil is well drained. Permeability is moderately slow. Runoff is negligible on 0 to 1 percent slopes, very low on 1 to 3 percent slopes, and low on 3 to 5 percent slopes.

USE AND VEGETATION: Mostly in rangeland. The remainder is used for cropland, orchards or wildlife. The major crops are forage sorghums and small grains. The climax plant community is a tall grass prairie. The dominant grass is little bluestem. Other plants include sideoats grama, vine mesquite, yellow Indiangrass, big bluestem, Canada wildrye, live oak, silver bluestem, Texas wintergrass, cane bluestem, hairy wedelia, Texas cupgrass, tall dropseed, and plains lovegrass. The dominant forbs include Maximilian sunflower, Engelmann daisy, and bushsunflower. The woody plants include elm, live oak, hackberry, bumelia, green briar and elbowbush. The site could potentially deteriorate to a plant population of sideoats grama, Texas wintergrass, cane bluestem, and buffalograss. Continued heavy use causes further deterioration and plants such as tumblegrass, hairy tridens, Texas grama, red threeawn, western ragweed, broomweed, prairie coneflower, and Ashe juniper, will dominate the site.

DISTRIBUTION AND EXTENT: Central Texas; Southwest Plateaus and Plains Range and Cotton Region, LRR-I: MLRA 81C-Edwards Plateau, Eastern Part; MLRA 81B-Edwards Plateau, Central Part; and MLRA 82A-Texas Central Basin. Southestwern Prairies Cotton and Forage Region, LRR-J: MLRA 85-Grand Prairie; and MLRA 87A-Texas Claypan Area, Southern Part. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Gillespie County, Texas; 1970.

REMARKS: Luckenbach soils were formerly in the Pedernales series which does not have a mollic epipedon. This soil was changed from a Typic Argiustoll to Udic Argiustoll in August 1989 because of change in Soil Taxonomy. However, most of the acreage and the typical pedon are located in the Typic Ustic moisture regime. Other areas are mainly on the Udic/Ustic and Typic/Ustic line. Therefore, we are classifying this soil in the Typic subgroup in 1990. NSSL lab data near the series type location in Gillespie County, Texas identified high shrink swell and slickensides suggesting a vertic subgroup. Classification was not changed pending a study over the entire series extent.

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 0 to 46 cm (0 to 18 in) (A horizons)
Argillic horizon: 46 to 97 cm (18 to 38 in) (Bt horizons)
Identifiable calcium carbonate: Secondary forms of calcium carbonate in all horizons below 76 cm (30 in).

ADDITIONAL DATA: Lab data available from the National Soil Survey Laboratory at type location on (pedon number: S09TX171002, sample numbers: 09N02891-09N02897.)

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

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National Cooperative Soil Survey
U.S.A.