Blackland Prairie Research Articles

Atrazine Loss in Runoff from No‐Tillage and Chisel‐Tillage Systems on a Houston Black Clay Soil

AbstractHerbicide concentration and mass load of runoff depends, to a large extent, on soil management. This study was conducted to determine how tillage impacts herbicide losses in runoff from a vertisol soil on the Blackland Prairie of Texas. Atrazine [6‐chloro‐N‐ethyl‐N′‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine] was applied at a rate of 2 kg a.i. ha−1 to a Houston Black clay soil (fine, montmorillonitic, thermic Udic Pellustert) in 1993 at the Blackland Research Center in Temple, TX. For 4 yr, the test area was under continuous management using a wide‐bed system with a wheat (Triticum aestivum L.), corn (Zea mays L.), and grain sorghum [Sorghum bicolor (L.) Moench] rotation. Tillage treatments consisted of no‐tillage or chisel‐tillage. All experiments were repeated four times. A rainfall simulator with an intensity of 12.5 cm h−1 was used to apply rainfall 24 h after the atrazine application. Sediment and runoff samples were collected during five time periods (from runoff initiation to 5, 5 to 10, 10 to 20, 20 to 30, and 30 to 40 min). No differences in atrazine concentrations were found among treatments in either the runoff water or sediment from any of the five time periods; however, crop residues prevented surface seal development and erosion resulting in reduced runoff and sediment losses. No‐tillage treatments significantly reduced runoff and sediment yield, rather than the atrazine concentration of the runoff, resulting in a 42% decrease of the atrazine load in the runoff and a 77% decrease in atrazine associated with the sediment. As a percentage of the total amount applied, runoff accounted for <2% of the atrazine. Sediment‐transported atrazine was much less important and represented <0.03% of the total amount applied.

Simulation of Sediment and Nitrate Loss on a Vertisol with Conservation Tillage Practices

Shrinking and swelling clay soils are dominant in the Blackland Prairie of Central Texas and comprise a vast majority of agricultural production land in the area. An agricultural field scale simulation model (EPIC) was applied on six small watersheds located in Riesel, Texas. A non-calibrated model performance evaluation of the runoff, sediment yield, nutrient transport, and crop growth components was completed. Management practices included no-till and conventional till systems. Annual and monthly predicted parameter values were compared with measured data for a 5-year period. Annual comparisons indicate close agreement between means and standard deviations for runoff, erosion, and nitrate-nitrogen. Significant correlation existed between monthly measured and simulated runoff and erosion. Significant correlation for nitrate-nitrogen was present in a majority of the cases studied. Prediction efficiency was significant for all elements except nitrate-nitrogen on two watersheds. The results of this study indicate EPICs ability to simulate natural processes without calibration on shrinking and swelling clay soils with varying management practices.

Tillage System Effects on Soil and Plant Nutrient Distributions on Vertisols

Heavy clay soils, such as vertisols of the Texas Blackland Prairie (Houston Black clay [fine, montmorillonitic, thermic Udic Pellusterts]), are difficult to manage for crop production. Such soils typically require high draft for tillage; have limited opportunities for mobility, tillage, and planting; and produce variable crop performance when associated with highly variable weather patterns. This study compared the soil and plant nutrient distributions and yield performance of an experimental no-till farming system with a farming system using modified conventional chisel-till soil management. Raised wide beds and controlled traffic were used for both systems [...]

Horizontal and Vertical Movements of Two Expansive Soils in Mississippi

AbstractExpansive soils create severe problems for road construction and maintenance, building foundations, and agricultural and industrial operations. Quantification of soil movement under natural field conditions has received little attention and is not well understood. Horizontal and vertical movements were measured for 20 mo by surveying rods placed at various depths in field plots of Typic Chromuderts and Vertic Hapludalfs of the Mississippi Blackland Prairie. Vertical soil movement was a function of soil depth, soil water content, and rainfall. Greatest vertical soil movement occurred in the upper 50 cm of both soils, with a maximum of 27 mm in the Vertisol and 24 mm in the Alfisol. Soil swelling occurred in winter and shrinking occurred in late spring and summer. Horizontal soil movement was not related to soil depth, but was related to soil water content and rainfall. Maximum horizontal movement was 36 mm in the Vertisol and 20 mm in the Alfisol. Horizontal and vertical movements in expansive soils are reversible, dynamic processes under natural field conditions. Horizontal movement appears more dynamic than vertical movement, and it reflects short‐term response to precipitation events followed by drier periods. Vertical movement reflects long‐term precipitation‐evapotranspiration distribution and is probably related to movement along master slickensides.

Effects of Polygyne Fire Ant Invasion on Native Ants of a Blackland Prairie in Texas

Effects of Polygyne Fire Ant Invasion on Native Ants of a Blackland Prairie in Texas

Assessing the relative efficiency of agricultural production units in the Blackland Prairie, Texas

The way in which data envelopment analysis (DEA) can be used to assess the relative technical efficiency of agricultural production units is illustrated. Two variants of the existing DEA additive model introduced, each eliminating earlier difficults encountered inapplication and theory. These new models are demonstrated through application to agricultural data obtained from the Blackland Prairie, Texas.

Design and Performance of A Bed-Forming Machine for Controlled-Traffic No-Tillage System

An experimental bed-forming machine was designed and developed for the operational conditions of controlled-traffic, no-tillage, cropping systems on the Texas Blackland Prairie. The machine was front mounted on a two-wheel-drive tractor to cut two spaced furrows and form raised wide beds when initiating such a tillage and cropping system. Subsequent rebedding was conducted after one or more cropping years, when the soil was covered with crop residues. The experimental machine was satisfactory in difficult clay soils. Alternative furrow plows could be used for other soil conditions.

Woolly Croton (Croton capitatus) and Bitter Sneezeweed (Helenium amarum) Control in the Blackland Prairie of Texas

Field studies were conducted in 1984 and 1986 to identify herbicides that would control woolly croton and bitter sneezeweed on grazing land in the Blackland prairies of Texas. Herbicides included chlorsulfuron, clopyralid, dalapon, dicamba, 2,4-D, glyphosate, metsulfuron, picloram, tebuthiuron, 2,4,5-T, and triclopyr. Chlorsulfuron and metsulfuron applied at 0.018 kg ha-1and 2,4-D, picloram, 2,4,5-T, and triclopyr at 0.28 kg ha-1controlled >80% of the woolly croton. Metsulfuron controlled more than 90% of the bitter sneezeweed at 0.018 kg ha-1. Similar control was obtained with clopyralid, glyphosate, and picloram each at 0.28 kg ha-1. Bermudagrass cover increased with all herbicide treatments except dalapon at one of three sites.

A No-Tillage Farming System for Clay Soils

(...) Our objective is to describe a no-tillage farming system which has been developed for Vertisol clay soils of the Texas Blackland Prairie and to review relevant research results. The system uses raised wide cropping beds, controlled traffic, crop rotations, and crop residue management technologies. Soil is protected, resource use is lowered, and crop yields are maintained. Crop rotation sequences included grain sorghum [Sorghum bicolor (L.) Moench], cotton (Gossypium hirsutum L.), wheat (Triticum aestivum L.), and corn (Zea mays L.) under dryland conditions. Step-by-step procedures are given for each crop. (...)

Height Growth of Loblolly and Slash Pine Plantations in the Northern Post-Oak belt of Texas

Abstract Age accounted for over 70% of the variation in tree height of 10- to 44-year-old loblolly pine (Pinus taeda L.) and slash (Pinus elliottii Engelm.) plantations established on deep sands, moderate sands, and nonsandy soils in the Northern Post-Oak Belt of Texas. Climatic and edaphicfactors, relating either directly or indirectly to the amount of moisture available for tree use, explained up to 17% of height growth variation. Height growth of the plantations was comparable to that of plantations growing in the pine-mixed hardwood forest cover type of East Texas. The NorthernPost-Oak Belt of Texas is an area approximately 50 to 100 miles wide located between the pine-mixed hard-wood forest type to the east and the black-land prairie to the west. Soils within the belt belong primarily to the Alfisol or Ultisol soil orders. The western-most areas of the belt receiveup to 20% less annual rain fall than the pine-mixed hardwood type of East Texas (U.S. Environmental Data and Information Service 1949-1982). The present forest of this area is dominated by post oak (Quercus stellata Wang.), black-jack oak (Quercus Marilandica Muench.), bluejack oak (Quercusincana Bartr.), and black hickory (Carya texana Buckl.) (Ward 1984). Loblolly pine (Pinus taeda L.) and shortleaf pine (Pinus echinata Mill.) occur naturally only in scattered locations (Wilson and Hacker 1986). South. j. Appl. For. 13(1):5-8.

The Site Contest for Fermilab

On 10 November the Department of Energy announced that the Superconducting Super Collider will be located on the Blackland Prairie corn and cotton fields around Waxahachie, Texas. The decision ended a competition entered by 25 states more than a year earlier. The contest for the SSC was reminiscent of way the site for Fermilab was chosen in 1966. Indeed, the procedure invented for selecting Fermilab was copied for the SSC, right down to the preliminary run-off refereed by a panel appointed by the National Academy of Sciences and the visits by a government team to the final few sites in the competition. Even the complaints from local citizens and the rumors of political influence that were rife during the Fermilab competition had their counterparts in the SSC contest.

Effect of Soil Depth and Erosion on Yield in the Mississippi Blacklands

AbstractFarmer fields were used 4 consecutive yr (1982–1985) to determine effects of soil depth and other parameters on soybean [Glycine max. (L.) Merr.] yield in the Mississippi Blackland Prairie. Soybean yields were sampled on 25 miniplots (1.8 m2) at each of two sites the first 2 yr and from six sites the third and fourth years. Soil depth ranged from 100 to 1500 mm across the miniplots at each site, and most plots had a silty clay texture. Soil samples were collected the second, third and fourth years from the 0‐ to 150‐mm depth and analyzed for pH, organic matter and extractable nutrients. Seasonal rainfall distribution was measured at each site the third and fourth years. Grain yields were variable from year to year for specific sites as well as from site to site within a given year. Regression analyses indicated that differences from site to site were due to variation in soil organic matter and rainfall distribution; whereas, differences within a site were influenced by organic matter, soil depth, and other parameters such as pH and available K which were related to depth. Grain yields ranged from near zero to over 2.5 Mg ha−1, depending on depth, organic matter content and seasonal rainfall distribution. Differences due to fertility were less pronounced. Soil depth was a much better predictor of yield at sites with low organic matter, especially when rainfall was also low. A regression model for depth vs. yield indicated that 10 mm of soil was worth an average of 0.006 Mg ha−1 of soybean grain within the 500‐ to 1500‐mm depth but worth 0.06 Mg ha−1 within the 50‐ to 150‐mm depth.

Host Plants of the Tarnished Plant Bug (Heteroptera: Miridae) in the Northern Blackland Prairies of Texas

Flowering herbaceous plants in the Northern Blackland Prairies of Texas were sampled with a sweepnet in 1982 and 1983. Plant species were classified as nonhosts, feeding hosts, or reproductive hosts of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois). Reproductive hosts were classified as early-season hosts, hosts supporting insect populations that move into cotton, or hosts providing insects for the next year's populations. Changing agronomic practices and plant succession, resulting in increased abundance of broad-leaved hosts, may be responsible for the increasing seriousness of tarnished plant bug pest status.

Nitrogen

Studies were conducted on two Blackland Prairie soils at Dallas, TX to determine the influence of clover plowed under on N nutrition of subsequent crops. Wheat yields were 103 and 86% of the yields obtained with 90 kg N/ha for the first and second crops after clover, respectively. Yields of nonfertilized wheat following fallow were 75 and 72% of the yield obtained with 90 kg N/ha for the first and second crops, respectively. Forage sorghum (non‐fertilized) grown as the first, second and third crop after clover produced 93, 80 and 43%, respectively, of the yields obtained with application of 90 kg N/ha. Nitrogen concentration in whole forage sorghum plants was 2.44 and 1.21% when grown as the first and third crop after clover, respectively. Nitrogen concentration in forage sorghum with N applied was 2.5%. These studies indicate that N from clover plowed under in Blackland soils may preclude N response by the first crop after clover. Some benefit may be obtained by the second crop but little if any...

Influence of Sulfur on Soil pH and Growth of Cenizo [Leucophyllum frutescens (Berl.) I.M. Johnst

Studies were conducted on two soils at Texas Agricultural Experiment Station (TAES) at Dallas to determine the influence of sulfur (S) application on soil pH and subsequent growth of cenizo (Leucophyllum frutescens). Application of 16800 kg/ha (7.5 Tons/A) reduced pH of Houston black clay from 7.6 to about 5.8 and application of 33600 kg/ha (15 T/A) reduced soil pH to 3.7. The same rates of S did not affect pH of Stephen silty clay because of the high CaCO3 found in the Stephen soil. The high S rate reduced growth and/or killed cenizo grown on Houston black clay but did not influence plant growth on Stephen silty clay. These studies indicate that the application of S to typical soils of the Blackland prairie is not necessary for improving growth of cenizo.

Geology of Dallas, Texas, United States of America

Dallas, the seventh largest city in the United States and the second largest city in Texas, lies within the Blackland Prairie physiographic province. The modern city, born on a “hardrock” crossing in the Trinity River in 1845, was also the site of many earlier Indian settlements dating to 11,000 B.C. The city is located on the updip edge of the Gulf Coastal Plain at the northwestern limit of the East Texas Embayment. A wedge of 610–1,372 m of Cretaceous age sedimentary rocks underlies the city. Paleozoic rocks of undetermined thickness are encountered below these units. Surficial deposits include, in ascending order, the Eagle Ford Shale, the Austin Chalk, the Ozan Formation (Taylor Marl) of Cretaceous age, and terraced alluvial deposits of Quaternary age. Soils consist of residual clays and silty clays (CH-CL) over bedrock and transported silty and sandy clays and gravels in terraced alluvial deposits and recent alluvium. Only three major constraints were identified in Dallas: expansive soils and bedrock, slope instability, and flooding. Most damage due to expansive soils is concentrated in areas of lightly loaded structures. Here techniques such as “pre-wetting,” lime stabilization and engineered slabs or pier and beam foundations systems are being utilized. Heavily loaded structures are usually tied into bedrock below the zone of seasonal moisture variation through means of drilled-shaft foundations. Most slope instability and flooding problems are administered through avant-garde hillslope and flood-plain ordinances. Dallas9s water supply is projected to be adequate through the year 2050. While surface water reservoirs are the major source of water, ground water, considered an emergency water source by the city, is being mined by private industry and surrounding municipalities at rates faster than apparent recharge. Solid waste is managed through a 4 km 2 landfill operation and is projected to be adequate for the next 50–75 years. Hazardous waste is transported to the Texas Gulf Coastal depositories.

Potato Leafhopper (Homoptera: Cicadellidae) Feeding on Seedling Cotton

In field studies at Dallas, Tex. in 1983, earliness (measured as number of bolls 3 weeks after first bloom) was negatively correlated with number of adult leafhoppers in D-Vac samples during June when cotton was grown according to Texas Agricultural Extension Service recommendations for integrated pest management. Greenhouse studies during 1985 using cotton seedlings of different ages caged with known numbers of potato leafhoppers, Empoasca fabae (Harris), demonstrated delayed initiation of squaring and reduction in number of squares in response to feeding of E. fabae . Potato leafhopper is reported for the first time as a pest of cotton in the northern Blackland Prairies of Texas.

Trifluralin-induced chlorosis in soybeans (Glycine max (L.) Merr.) grown on clayey, high pH soils

The cause of leaf chlorosis, frequently observed on soybeans (Glycine max (L.) Merr.) grown on high pH soils of the Mississippi Blackland Prairie, is thought to be low Fe availability and restricted rooting. Three greenhouse experiments were conducted using two soils, Sumter, a Rendollic Eutrocrept and Okolona, a Typic Chromudert; nine soybean cultivars differing in Feefficiency; and trifluralin (α-α-α-trifluoro-2,6-dinitro-N, N-di-propyl-p-toludine). Trifluralin at rates greater than 0.56 kg/ha caused chlorosis which was more severe on the Sumter, a soil low in available Fe. Fe-efficient cultivars were more resistant to the chlorosis induced by trifluralin than the Fe-inefficient cultivars. It was concluded that the chlorosis is an Fe deficiency caused by reduced uptake. The herbicide-induced chlorosis can be avoided by proper dosage and placement of the herbicide.

Wheat and Forage Sorghum Response to Residual Phosphorus in Blackland Soils1

AbstractPhosphorus fertilizers are generally applied for crops grown on Blackland Prairie soils of Texas, but the crop yield response due to residual P from single applications of P is unknown. Studies were conducted over a 5‐yr period (1977 to 1981) on Austin silty clay (fine‐silty, carbonatic, thermic Entic Haplustolls) and Dalco clay (fine, montmorillonitic, thermic Udic Pellusterts) soils to evaluate the residual effects of P on subsequent crops. Fertilizer rates of 0, 25, and 50 kg P ha−1were applied in 1977,1978, and 1979 at three sites with soil P levels of 6,10, and 13 mg kg−1NaHCO3‐extractable P (0 to 15 cm depth). Following the initial crop year, plots were split to include 25 kg P ha−1with the seed. The other half received no fertilizer P other than the initial P application. The test crops were wheat (Triticum aestivumL.), forage sorghum (Sorghum bicolorL. Moench), and sweet clover (Melilotus albusLam.). A significant yield increase due to initial P application was obtained at each site. Crop yield increases due to residual effects of the 50 kg P ha−1rate ranged from 0 to 20%, while yield increases due to 25 kg P ha−1at planting ranged from 19 to 43%. Percent yield increase from residual P was greater on soil with 6 mg kg−1soluble P than on soil with 13 mg kg−1soluble P. Phosphorus concentrations in wheat plants were increased by residual P, but were much higher in plants receiving P at planting. These data indicate that some yield increase can be expected from residual P from a single application of moderate amounts of P. For more efficient use of P and high yields, P should be applied to each crop if initial NaHCO3‐extractable P levels are between 6 and 13 mg kg−1.

Composition, Classification and Species Response Patterns of Remnant Tallgrass Prairies in Texas

Thirty-five remnant upland grasslands within the Blackland, San Antonio, Fayette and Upper Coastal prairies were sampled for species frequency, foliage cover and richness. PCA ordination and cluster analysis were used to ordinate and classify these communities. The majority of these grasslands are dominated by Schizachyrium scoparium with Sorghastrum nutans the second most important species. Andropogon gerardii and Bouteloua curtipendula increase in importance with increasing soil clay content, organic matter and pH and decreasing total annual precipitation. Paspalum plicatulum becomes an important secondary species in communities over acid Alfisols in the Fayette Prairie and acid Alfisols and Vertisols of the Upper Coastal Prairie. High precipitation ( > 90 cm) areas over Alfisols at the northern end of the Blackland Prairie support a unique grassland dominated by Sporobolus silveanus with Carex meadii as an important secondary species. In this same area on Vertisols communities are found that are dominated by Tripsacum dactyloides and Panicum virgatum. Species respond independently and continuously along soil and climatic gradients except where locally sharp transitions occur between Alfisols and Vertisols. Species diversity did not vary significantly among communities. Soil pH was positively correlated with species richness, which was related to slightly higher richness of stands on Alfisols whici. have low pH, and slightly higher richness of Coastal Prairie stands which also have generally lower pH values. INTRODUCTION The Blackland, Fort Worth, San Antonio, Fayette and Upper Coastal prairies occupy a N-S strip comprising approximately 8 million ha within E central Texas (Godfrey et al., 1973) (Fig. 1). Native vegetation of these grasslands has largely been destroyed by cultivation, overgrazing and urbanization. Although several authors have described these prairies (Dyksterhuis, 1946; Launchbaugh, 1955; Collins et al., 1975; Butler, 1979; Diamond, 1983; Smeins and Diamond, 1983), no attempt has been made to compare patterns of community composition and species diversity among them. The Upper Coastal Prairie has traditionally been separated from other Texas prairies (Tharp, 1926; Gould, 1975), but lack of quantitative data makes an evaluation of the degree of relationship among the Coastal Prairie and other Texas prairies impossible. This study provides quantitative data on vegetation and soils of uplands within the Blackland, Fayette, San Antonio and Upper Coastal prairies. These data allow detailed analysis of Texas grasslands to: (1) determine relationships among communities; (2) evaluate species-to-species and species-to-environment relationships; (3) clarify classification, and (4) evaluate patterns in species diversity. STUDY AREA Location and extent. -The grasslands studied are located in a N-S strip approximately 300 km wide and 100 km long in E and central Texas (Fig. 1). To the N the Blackland Prairie borders on the Red River, whereas to the S the Coastal Prairie grades into the Gulf Coast marshes. The eastern border is defined by the Post Oak Savannah, while the western border is defined by the western Cross Timbers in the N, the Edwards Pla-