Ecological Research Evaluation

Hays County 4

 

 

 

 

Acreage:  Approximately 290 acres

County:    Hays

Nearest Town:  Wimberley         

General Property Location:  Approximately eight miles west of Wimberley, two miles north of FM 2325.

 

Photo Point 1:  Representative view of riparian woodland.  Tree layer consists of cedar elm, live oak, mature juniper, and escarpment black cherry.  Shrubs present in photo are regrowth cedar.  Canopy is closed in some areas.  Shade tolerant herbaceous plant layer including purpletop tridens and Scribner’s rosette grass. 

 

 Photo point 2:   View of juniper/live oak parkland.  Very shallow soil site.  Herbaceous layer dominated by little bluestem, tall grama, and seep muhly.  Live oak tree in background. 

 

Photo point 3:   Old terraced field being invaded by regrowth juniper.  Dominant herbaceous plants in terraced field include little bluestem, silver bluestem, buffalograss, and others.  Field bordered by heavy oak/juniper woodland. 

 

Photo point 4:   Representative view of live oak/juniper parkland.  Some Spanish oaks and escarpment black cherries in the upland parklands. 

 

Photo point 5:   View of oak/juniper parkland.  Closed canopy in some areas.  Late successional herbaceous layer result of lack of recent grazing activity. 

 

 

Site Description

 

This irregularly-shaped 290-acre property is located approximately eight miles west of Wimberley, Texas, about 2 miles north of FM 2325.  South Onion Creek and several of its tributaries run from west to east through the property.  The creek is intermittent in nature.  Several small ponds are present on the property, though they were dry during the time of the site visit (10/31/2005).  The terrain is moderately sloped in an easterly direction.  Elevations range from approximately 1390 ft MSL to 1450 ft MSL.  While a large portion of perimeter fencing is in poor condition, a portion of the perimeter fencing is high-fenced and in good condition. 

 

Habitat Description

 

Multiple habitat types are present on the property.  The most dominant habitat type is a juniper/oak parkland, though woodlands, riparian corridors, and open fields are also present.  These habitats are dispersed throughout the property creating a mosaic across the property.  The percentage of canopy cover varied widely, but averaged around 40%.  Dominant tree species included juniper and live oak, though Spanish oak, escarpment black cherry, and cedar elm were also found.  Though not observed during the site visit, one Texas madrone is reported to be on the property.  The shrub layer consists of regrowth juniper, agarita, persimmon, redbud, flameleaf sumac, evergreen sumac.  Due to lack of heavy grazing pressure in the past, the herbaceous community on most of the property is in excellent condition, and the parkland habitats were no exception.  Little bluestem, tall grama, seep muhly, orange zexmania, and silver bluestem dominated the shallow-soil sites while little bluestem, King Ranch bluestem, Lindheimer muhly, Mexican hat, and frostweed were observed on deeper soils.  Some of the historic livestock watering and feeding areas had significant levels of bermudagrass, Mexicant hat, and western ragweed. 

 

Juniper oak woodlands were present in many areas, particularly areas with greater slopes.  Tree composition were similar to those found in the parklands (dominated by juniper, live oak, with some Spanish oak), but woodland sites differed from the parkland sites by having 80-100% canopy cover levels for trees and less abundant herbaceous and shrub layers.  The shrub community in shaded environments included regrowth juniper, persimmon, and elbowbush. 

 

One of the more wildlife-conducive habitats on the property was the series of riparian woodlands along South Onion Creek and its tributaries.  The overstory layer was more diverse and included cedar elm, live oak, escarpment black cherry, Spanish oak, sugar hackberry, and mature juniper.  Shrubs included regrowth juniper, spicebush, elbowbush, and American beautyberry.  The herbaceous plant community was abundant and included purpletop tridens, fall witchgrass, Scribner’s rosette grass, and Lindheimer muhly. 

 

A 16-acre terraced field can be found on the western end of the property.  This field consists of little bluestem, silver bluestem, buffalograss, and several others.  Most of the junipers invading this field are between 5 and 10 years of age.  

 

The only exotic plant observed in significant quantities was King Ranch bluestem.  The introduced grass was usually found in more open habitat, usually on deeper soils. 

 

 

Soil Descriptions:

 

The study property consisted of six soil types. 

 

BrB  -  Bolar clay loam, 1 to 3 percent slopes

 

Bolar soils make up 85 percent of the map unit.  The depth to a restrictive feature is 20 to 40 inches to a bedrock (paralithic). It is well drained.  The slowest soil permeability within a depth of 60 inches is moderate.  Available water capacity to a depth of 60 inches is low, and shrink swell potential is moderate.  Annual flooding is none, and annual ponding is none.  The minimum depth to a water table is greater than 6 feet.  This component is in the Clay Loam ecological site. 

Climax plants are predominantly little bluestem with indiangrass, big bluestem, switchgrass, vine-mesquite, sideoats grama, elm, live oak, hackberry; and many forbs such as Maximilian sunflower, engelmanndaisy, bushsunflower, halfshrub sundrop, and ratany.

 

BtD : Brackett – Rock outcrop – Comfort soils complex, undulating slopes

 

Brackett-Rock outcrop-Comfort soils complex, undulating slopes soil series, which is composed of shallow, loamy, and occasionally clayey soils interspersed with limestone bedrock outcroppings.  The soil is moderately alkaline (pH 7.9 – 8.4).  These soils range from 11 – 17 inches in total depth.  They are well drained, have a modernly slow permeability with very low available water capacity and a shallow rooting zone.  Runoff is rapid and water erosion is a severe hazard.  A distinguishing feature of Brackett soils is a benched or stair-stepped appearance due to the bands of rock outcrop.  BtG is in the Adobe ecological site.  For the Adobe ecological site, grasses make up about 80 percent of the potential historic climax plant community, and woody plants and forbs make up the rest.  Typically, little bluestem makes up about 50 percent of the vegetation; indiangrass, 5 percent; sideoats grama and tall grama, 15 percent; other midgrasses, such as muhlys, green sprangletop, dropseeds, hairy grama, perennial threawn, tridens and sedges, 15 percent.  Woody plants, such as live oak and Spanish oak, make up about 10 percent; and forbs, such as orange zexmenia, prairie-clover, daleas, and vetch, make up 5 percent.

 

 

Comfort-Rock outcrop complex, undulating (CrD)

 

The CrD soil complex is mostly composed of Comfort very stony clay and consists of shallow clayey soils on hilltops and ridges.  Cobbles and stones frequently cover nearly 45% of the surface of these areas.  Overall soil depth is typically 13 inches.  CrD soils are mildly alkaline (pH 7.4 – 7.8), well drained and slowly permeable with a very low available water capacity and shallow rooting depth.  Runoff is slow to moderate and the hazard of water erosion is slight.  The CrD complex is classified in the Low Stony Hills ecological site.  The potential plant community is a live oak savannah.  Typically, little bluestem makes up 50 percent of the plant community; indiangrass and big bluestem, 20 percent; other midgrasses, such as wildrye, sideoats grama, Texas cupgrass, plains lovegrass, green sprangletop, dropseed, silver bluestem, etc., 15 percent; woody plants, such as live oak, elm, and hackberry, 10 percent; and forbs such as orange zexmenia, bush sunflower, bundleflower, prairie-clover, milk pea, snapbean, and Engelmann-daisy, 5 percent. 

 

Map Unit:  DoC  -  Doss silty clay, 1 to 5 percent slopes

 

This map unit is in the Edwards Plateau, Eastern Part (proposed) Major Land Resource Area.  Doss soils make up 85 percent of the map unit.  The depth to a restrictive feature is 11 to 20 inches to a bedrock (paralithic). It is well drained.  The slowest soil permeability within a depth of 60 inches is moderately slow.  Available water capacity to a depth of 60 inches is very low, and shrink swell potential is moderate.  Annual flooding is none, and annual ponding is none.  The minimum depth to a water table is greater than 6 feet.  The maximum calcium carbonate equivalent within a depth of 40 inches is 70 percent.  In the profile, there are no saline horizons, and there are no sodic horizons.  It is nonirrigated land capability subclass 4e. Very shallow and shallow clayey uplands less than 20 inches thick; medium natural fertility; droughty very low to low water holding capacity with poor plant-soil-moisture relationship; low production potential.  This soil is classified in the Shallow PE 44+ ecological site.  Climax vegetation is big and little bluestems, indiangrass, sideoats and tall gramas, cane bluestem, plains lovegrass, maximilian sunflower, bushsunflower, engelmanndaisy, orange zexmenia, daleas, gayfeather, sundrops, penstemon, heath aster, prairieclover, prairie bluets, and bundleflower, with scattered live oak.

 

RcD - Real-Comfort-Doss, complex, undulating

 

The RcD soil complex is composed of shallow, loamy and occasionally clayey soils interspersed with limestone bedrock outcroppings. The complex is moderately alkaline (pH 7.9 – 8.4). These soils range from 11 – 17 inches in total depth. They are well drained, have a modernly slow permeability with very low available water capacity and a shallow rooting zone. Runoff is rapid and water erosion is a severe hazard.  A distinguishing feature of this soil complex is a benched or stair-stepped appearance due to the bands of rock outcrop. RcD is in the Adobe ecological site.  Climax vegetation is savannah of little bluestem, indiangrass, tall grama, tall dropseed, sideoats grama, oaks, blackfoot daisy, orange zexmenia, dalea, bundleflower, and sundrop. Juniper invades the site.

 

 

Sunev clay loam, 1 to 3 percent slopes (SuB)

 

Sunev clay loam is a well drained, deep, gently sloping soil found in valleys and foot slopes. The topsoil extends to 11 inches deep with a total soil depth of 35 inches. The soil is moderately alkaline and contains 45% calcium carbonate (lime) on average. Water runoff is medium to rapid, permeability is moderate and available water capacity is moderate. The rooting zone in Sunev clay is deep and water erosion is only a moderate hazard. This soil is well suited for cropland, pastures, and rangeland. It produces a larger diversity of productive grasses and wildflowers, along with desirable trees and shrubs, when properly managed as a rangeland. This diversity of plants provides an adequate food, cover, and shelter for many wildlife species. This soil is classified in the Clay Loam range site.  The potential plant community is a true prairie.  Typically, little bluestem makes up 30 percent of the plant community; indiangrass, 10 percent; big bluestem, 5 percent; other midgrasses such as tall dropseed, silver bluestem, sideoats grama, buffalograss, perennial threeawn, and Texas wintergrass, 50 percent; and forbs such as Engelmann-daisy, bundleflower, sensitivebrier, and bush sunflower, 5 percent. 

 

 

Research Possibilities

 

The property’s large size, variety of habitats and soils, and the presence of an intermittent creek and its tributaries would lend itself to a wide variety of research projects.  The property has not had recent grazing pressure, and the plant communities reflect this fact. 

 

The property’s most unique features are the riparian plant communities around South Onion Creek and its tributaries.   While the intermittent water flows of the creek and the lack of consistent ponds on the property don’t lend themselves to aquatic studies, these communities are in excellent health and numerous flora/fauna studies can be undertaken.      

 

 

 

Keith Olenick

Senior Wildlife Biologist

Plateau Land & Wildlife Management

October 31, 2005