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South Dakota State University

Agronomy, Horticulture and Plant Science Faculty Publications

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Articles 121 - 145 of 145

Full-Text Articles in Life Sciences

Detecting Shifts In Soil Microbial Community Structure And Function Post Landspread Of Manure Or Biosolids Containing Antimicrobial Chemicals, Kelly Lehnert, Sharon A. Clay, Susan Gibson, Volker Brozel Nov 2007

Detecting Shifts In Soil Microbial Community Structure And Function Post Landspread Of Manure Or Biosolids Containing Antimicrobial Chemicals, Kelly Lehnert, Sharon A. Clay, Susan Gibson, Volker Brozel

Agronomy, Horticulture and Plant Science Faculty Publications

Soil microbial diversity and community interaction play an indispensable role in 2,4-dichorophenoxyacetic acid (2,4-D) herbicide degradation. The addition of manure or municipal waste biosolids through landspreading may alter soil community structure and function if these materials contain antimicrobial chemicals like chlortetracycline (CTC), administered in livestock feed to promote animal growth and health or tetracycline (TET) utilized in human health. In this study, soil applied with manure collected from pigs fed standard CTC levels was compared to soil containing manure from control pigs fed no CTC, and a comparison of soil applied with biosolids containing TET or without TET to distinguish …

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Common Waterhemp Growth And Fecundity As Influenced By Emergence Date And Competing Crop, E. Uscanga-Mortera, S. Clay, F. Forcella, J. Gunsolus Aug 2007

Common Waterhemp Growth And Fecundity As Influenced By Emergence Date And Competing Crop, E. Uscanga-Mortera, S. Clay, F. Forcella, J. Gunsolus

Agronomy, Horticulture and Plant Science Faculty Publications

Common waterhemp (Amarathus rudis Sauer) is a frequent weed in glyphosate-resistant (GR) crops in the midwestern USA due, in part, to the delayed emergence of its seedlings. Variable waterhemp emergence was simulated by transplanting seedlings into both corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] and bare plot areas at differing crop growth stages during two growing seasons in western Minnesota. Growth and fecundity were measured. As expected, late planted weeds produced little dry matter and few seeds, and competition from corn or soybean reduced waterhemp dry weight and fecundity by 90% compared with isolated plants. Interestingly, common …

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Microarray Analysis Of Late-Season Velvetleaf (Abutilon Theophrasti) Effect On Corn, David P. Horvath, Robert Gulden, Sharon A. Clay Dec 2006

Microarray Analysis Of Late-Season Velvetleaf (Abutilon Theophrasti) Effect On Corn, David P. Horvath, Robert Gulden, Sharon A. Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Microarray analysis was used to identify changes in gene expression in corn leaves collected from plants at the V11–14 growth stage that resulted from competition with velvetleaf. The plants were grown in field plots under adequate N (addition of 220 kg N ha1) and irrigation to minimize N and water stress. Consequently, only differences resulting from competition for micronutrients, light, and perhaps allelopathic stress were anticipated. Genes involved in carbon and nitrogen utilization, photosynthesis, growth and development, oxidative stress, signal transduction, responses to auxin and ethylene, and zinc transport were repressed in corn growing in competition with velvetleaf. …

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Spatial Distribution, Temporal Stability, And Yield Loss Estimates For Annual Grasses And Common Ragweed (Ambrosia Artimisiifolia) In A Corn/Soybean Production Field Over Nine Years, Sharon A. Clay, Bruce Kreutner, David E. Clay, Cheryl Reese, Jonathan Kleinjan, Frank Forcella Jan 2006

Spatial Distribution, Temporal Stability, And Yield Loss Estimates For Annual Grasses And Common Ragweed (Ambrosia Artimisiifolia) In A Corn/Soybean Production Field Over Nine Years, Sharon A. Clay, Bruce Kreutner, David E. Clay, Cheryl Reese, Jonathan Kleinjan, Frank Forcella

Agronomy, Horticulture and Plant Science Faculty Publications

Weeds generally occur in patches in production fields. Are these patches spatially and temporally stable? Do management recommendations change on the basis of these data? The population density and location of annual grass weeds and common ragweed were examined in a 65-ha corn/soybean production field from 1995 to 2004. Yearly treatment recommendations were developed from field means, medians, and kriging grid cell densities, using the hyperbolic yield loss (YL) equation and published incremental YL values (I ), maximum YL values (A), and YL limits of 5, 10, or 15%. Mean plant densities ranged from 12 to 131 annual grasses m22 …

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Sorption-Desorption Of Imidacloprid And Its Metabolites In Soil And Vadose Zone Materials, Sharon V. Papiernik, William C. Koskinen, Lucia Cox, Pamela J. Rice, Sharon A. Clay, Nancy R. Werdin-Pfisterer, Kristen A. Norberg Jan 2006

Sorption-Desorption Of Imidacloprid And Its Metabolites In Soil And Vadose Zone Materials, Sharon V. Papiernik, William C. Koskinen, Lucia Cox, Pamela J. Rice, Sharon A. Clay, Nancy R. Werdin-Pfisterer, Kristen A. Norberg

Agronomy, Horticulture and Plant Science Faculty Publications

Sorption-desorption is one of the most important processes affecting the leaching of pesticides through soil because it controls the amount of pesticide available for transport. Subsurface soil properties can significantly affect pesticide transport and the potential for groundwater contamination. This research characterized the sorption-desorption of imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-Nnitro-2-imidazolidinimine) and three of its metabolites, 1-[(6-chloro-3-pyridinyl)methyl]-2-imidazolidinone (imidacloprid-urea), 1-[(6-chloro-3-pyridinyl)methyl]-4,5-dihydro-1H-imidazol-2-amine (imidaclopridguanidine), and 1-[(6-chloro-3-pyridinyl)methyl]-1H-imidazol-2-amine (imidacloprid-guanidine-olefin), as a function of changing soil properties with depth in two profiles extending from the surface to a depth of 1.8 or 8 m. Sorption of each compound was highly variable and hysteretic in all cases. Normalizing the sorption coefficients (Kf) …

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Theoretical Derivation Of Stable And Nonisotopic Approaches For Assessing Soil Organic Carbon Turnover, D. E. Clay, C. G. Carlson, S. A. Clay, C. Reese, Z. Liu, J. Chang, M. M. Ellsbury Jan 2006

Theoretical Derivation Of Stable And Nonisotopic Approaches For Assessing Soil Organic Carbon Turnover, D. E. Clay, C. G. Carlson, S. A. Clay, C. Reese, Z. Liu, J. Chang, M. M. Ellsbury

Agronomy, Horticulture and Plant Science Faculty Publications

Techniques for measuring soil organic C (SOC) turnover in production fields are needed. The objectives of this study were to propose and test nonisotopic and 13 C stable isotopic techniques for assessing SOC turnover. Based on SOC equilibrium and mass balance relationships, an equation was derived: NHC/SOC initial=[1/(SOC× k NHC)](dSOC/dt)+ k SOC/k NHC, where dSOC/dt is the annual change in SOC, NHC is nonharvested C returned to soil, k SOC is the annual mineralization rate of SOC, and k NHC is the annual mineralization rate of NHC. This equation was used to calculate maintenance rates. An isotopic approach based on …

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Interactions Among Western Corn Rootworm (Coleoptera: Chrysomelidae), Yellow Foxtail, And Corn, M. M. Ellsbury, K. R. Banken, S. A. Clay, F. Forcella Jun 2005

Interactions Among Western Corn Rootworm (Coleoptera: Chrysomelidae), Yellow Foxtail, And Corn, M. M. Ellsbury, K. R. Banken, S. A. Clay, F. Forcella

Agronomy, Horticulture and Plant Science Faculty Publications

Field studies at sites with two contrasting soil types investigated effects from the presence of yellow foxtail [Setaria pumila (Poir.) Roem. and Schult.], established in bands parallel to corn rows, on western corn rootworm (Diabrotica virgifera virgifera LeConte) survival, corn root injury, lodging, biomass production, and yield. Results suggested that the presence of foxtail as an alternate host inßuenced the degree and progression of corn rootworm damage and adult emergence in a givenlocality. Rootworm adults emergedlater from foxtail band areas and had smaller head capsule size than did individuals from areas without foxtail, consistent with earlier Þndings that foxtail in …

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Factors Influencing Spatial Variability Of Soil Apparent Electrical Conductivity, D. E. Clay, J. Chang, D. D. Malo, C. G. Carlson, C. Reese, S. A. Clay, M. Ellsbury, B. Berg Jan 2001

Factors Influencing Spatial Variability Of Soil Apparent Electrical Conductivity, D. E. Clay, J. Chang, D. D. Malo, C. G. Carlson, C. Reese, S. A. Clay, M. Ellsbury, B. Berg

Agronomy, Horticulture and Plant Science Faculty Publications

Soil apparent electrical conductivity (ECa) can be used as a precision farming diagnostic tool more efficiently if the factors influencing ECa spatial variability are understood. The objective of this study was to ascertain the causes of ECa spatial variability in soils developed in an environment with between 50 and 65 cm of annual rainfall. Soils at the research sites were formed on calcareous glacial till parent materials deposited approximately 10,000 years ago. Soil samples (0–15 cm) collected from at least a 60 by 60 m grid in four fields were analyzed for Olsen phosphorus (P) and …

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Herbicide Movement And Dissipation At Four Midwestern Sites, S. A. Clay, R. H. Dowdy, J. A. Lamb, J. L. Anderson, B. Lowery, R. E. Knight, D. E. Clay May 2000

Herbicide Movement And Dissipation At Four Midwestern Sites, S. A. Clay, R. H. Dowdy, J. A. Lamb, J. L. Anderson, B. Lowery, R. E. Knight, D. E. Clay

Agronomy, Horticulture and Plant Science Faculty Publications

This study was conducted to evaluate atrazine (2‐chloro‐4‐ethylamino‐6‐isopropyl‐1, 3, 5‐triazine) and alachlor (2‐chIoro‐N‐(methoxymethyl)acetamide) dissipation and movement to shallow aquifers across the Northern Sand Plains region of the United States. Sites were located at Minnesota on a Zimmerman fine sand, North Dakota on Hecla sandy loam, South Dakota on a Brandt silty clay loam, and Wisconsin on a Sparta sand. Herbicide concentrations were determined in soil samples taken to 90 cm four times during the growing season and water samples taken from the top one m of aquifer at least once every three months. Herbicides were detected to a …

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Precision Farming Protocols. Part 2. Comparison Of Sampling Approaches For Precision Phosphorus Management, David E. Clay, Jiyul Chang, C. Gregg Carlson, Doug Malo, Sharon A. Clay, Mike Ellsbury Jan 2000

Precision Farming Protocols. Part 2. Comparison Of Sampling Approaches For Precision Phosphorus Management, David E. Clay, Jiyul Chang, C. Gregg Carlson, Doug Malo, Sharon A. Clay, Mike Ellsbury

Agronomy, Horticulture and Plant Science Faculty Publications

Research is needed to compare the different techniques for developing site‐specific phosphorus (P) recommendations on a field‐wide basis. The objective of this study was to determine the impact different techniques for developing site‐specific P recommendation maps on yield and profitability. Enterprise analysis combined with a crop simulation model and detailed field characterization was used to estimate the value of spatial P information in a system where N was not limiting. The systems evaluated were continuous corn (Zea mays) and corn and soybean (Gfycine max) rotations where sampling and fertilizer applications were applied annually and semi‐annually, respectively. The sampling techniques tested …

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Sampling Weed Spatial Variability On A Fieldwide Scale, Sharon A. Clay, G. Jason Lems, Frank Forcella, Michael M. Ellsbury, C. Gregg Carlson, David E. Clay Dec 1999

Sampling Weed Spatial Variability On A Fieldwide Scale, Sharon A. Clay, G. Jason Lems, Frank Forcella, Michael M. Ellsbury, C. Gregg Carlson, David E. Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Site-specific weed management recommendations require knowledge of weed species, density, and location in the field. This study compared several sampling techniques to estimate weed density and distribution in two 65-ha no-till Zea mays–Glycine max rotation fields in eastern South Dakota. The most common weeds (Setaria viridis, Setaria glauca, Cirsium arvense, Ambrosia artemisiifolia, and Polygonum pensylvanicum) were counted by species in 0.1-m2 areas on a 15- by 30-m (1,352 points in each field) or 30- by 30-m (676 points in each field) grid pattern, and points were georeferenced and data spatially analyzed. Using different sampling approaches, weed populations were estimated by …

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Influence Of Deleterious Rhizobacteria On Leafy Spurge (Euphorbia Esula) Roots, Mark A. Brinkman, Sharon A. Clay, Robert J. Kremer Dec 1999

Influence Of Deleterious Rhizobacteria On Leafy Spurge (Euphorbia Esula) Roots, Mark A. Brinkman, Sharon A. Clay, Robert J. Kremer

Agronomy, Horticulture and Plant Science Faculty Publications

Rhizobacteria have been shown to be phytotoxic to leafy spurge in laboratory assays. This field study investigated the influence of two strains of Pseudomonas fluorescens [Trevisan, (Migula)], deleterious rhizobacteria (DRB), on root weight, root bud number, and root carbohydrate content of leafy spurge at three sites located in northeast and north-central South Dakota. Soils were inoculated with 2 g of starch-based granules containing no bacteria or starch granules containing 108colony-forming units (cfu)/g of either bacterial strain LS102 (Montana origin) or LS174 (South Dakota origin). Bacterial strains were detected on root samples from treated areas. Root weight and root carbohydrate content …

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Precision Farming Protocols: Part 1. Grid Distance And Soil Nutrient Impact On The Reproducibility Of Spatial Variability Measurements, Jiyul Chang, David E. Clay, C. Greg Carlson, Douglas D. Malo, Sharon A. Clay, John Lee, Mike Ellsbury Nov 1999

Precision Farming Protocols: Part 1. Grid Distance And Soil Nutrient Impact On The Reproducibility Of Spatial Variability Measurements, Jiyul Chang, David E. Clay, C. Greg Carlson, Douglas D. Malo, Sharon A. Clay, John Lee, Mike Ellsbury

Agronomy, Horticulture and Plant Science Faculty Publications

To determine temporal changes in soil nutrient status, reproducible results must be obtained at each time step. The objective of this paper was to determine the impact of grid distance on the reproducibility of spatial variability measurements. Soil samples from the 0 to 15 cm depth were collected from a 30 by 30 m grid in May 1995 in a 65 ha notill corn (Zea mays L.) field. Each bulk sample contained 15 individual cores, collected at sample points located every 11.4 cm along a transect that transversed 3 corn rows (57 cm). At each sampling point latitude, longitude, elevation, …

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Influence Of Crop Rotation, Tillage, And Management Inputs On Weed Seed Production, George O. Kegode, Frank Forcella, Sharon Clay Apr 1999

Influence Of Crop Rotation, Tillage, And Management Inputs On Weed Seed Production, George O. Kegode, Frank Forcella, Sharon Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Approaches to crop production that successfully reduce weed seed production can benefit farming systems by reducing management inputs and costs. A 5-yr rotation study was conducted in order to determine the effects that interactions between crop rotation, tillage, and amount of herbicide and fertilizer (management inputs) have on annual grass and broad-leaved weed seed production and fecundity. There were 10 crop rotation and tillage system combinations and three levels of management inputs (high, medium, and low). Green and yellow foxtail were the major weed species, and together they yielded between 76 and 93% of collected weed seeds. From 1990 to …

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Field Scale Variability Of Nitrogen And Δ15n In Soil And Plants, D. E. Clay, J. Chang, S. A. Clay, M. Ellsbury, C. G. Carlson, D. D. Malo, D. Woodson, T. Desttur Nov 1998

Field Scale Variability Of Nitrogen And Δ15n In Soil And Plants, D. E. Clay, J. Chang, S. A. Clay, M. Ellsbury, C. G. Carlson, D. D. Malo, D. Woodson, T. Desttur

Agronomy, Horticulture and Plant Science Faculty Publications

Understanding the factors that influence soil and plant nitrogen (N) spatial variability may improve our ability to develop management systems that maximize productivity and minimize environmental hazards. The objective of this study was to determine the field (65 ha) scale spatial variability of N and δ15N in soil and corn (Zea mays). Soil, grain, and stover samples were collected from grids that ranged in size from 30 by 30 m to 60 by 60 m. Plant samples, collected following physiological maturity in 1995, were analyzed for total N and δ15N. Soil samples, collected prior …

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Diversity And Dominant Species Of Ground Beetle Assemblages (Coleoptera: Carabidae) In Crop Rotation And Chemical Input Systems For The Northern Great Plains, Michael M. Ellsbury, Janine E. Powell, Frank Forcella, W. David Woodson, Sharon A. Clay, Walter E. Riedell Sep 1998

Diversity And Dominant Species Of Ground Beetle Assemblages (Coleoptera: Carabidae) In Crop Rotation And Chemical Input Systems For The Northern Great Plains, Michael M. Ellsbury, Janine E. Powell, Frank Forcella, W. David Woodson, Sharon A. Clay, Walter E. Riedell

Agronomy, Horticulture and Plant Science Faculty Publications

Dominant carabid species present in crops and crop rotation sequences commonly used in the northern Great Plains were assessed as an initial step toward the management of carabids as natural control agents. Ground beetle populations were determined by pitfall trapping in 4 crop rotation treatments maintained under high, managed, and low levels of chemical fertilizer and pesticide inputs. Diversity and species richness among crops, rotations, and input levels were compared using 3 indices—the Shannon-Weaver Index, relative diversity, and the Hierarchical Richness Index (HRI). Four carabid species, Cyclotrachelus altemans (Casey), Poecilvs lucublandus Say, Harpalns pensylvanicus (DeGeer), and Bembidion quadrimaculatum L., comprising …

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Diversity And Dominant Species Of Ground Beetle Assemblages (Coleoptera: Carabidae) In Crop Rotation And Chemical Input Systems For The Northern Great Plains, Michael M. Ellsbury, Janine E. Powell, Frank Forcella, W, David Woodson, Sharon A. Clay, Walter E. Riedell Sep 1998

Diversity And Dominant Species Of Ground Beetle Assemblages (Coleoptera: Carabidae) In Crop Rotation And Chemical Input Systems For The Northern Great Plains, Michael M. Ellsbury, Janine E. Powell, Frank Forcella, W, David Woodson, Sharon A. Clay, Walter E. Riedell

Agronomy, Horticulture and Plant Science Faculty Publications

Dominant carabid species present in crops and crop rotation sequences commonly used in the northern Great Plains were assessed as an initial step toward the management of carabids as natural control agents. Ground beetle populations were determined by pitfall trapping in 4 crop rotation treatments maintained under high, managed, and low levels of chemical fertilizer and pesticide inputs. Diversity and species richness among crops, rotations, and input levels were compared using 3 indices—the Shannon-Weaver Index, relative diversity, and the Hierarchical Richness Index (HRI). Four carabid species, Cyclotrachelus altemans (Casey), Poecilvs lucublandus Say, Harpalns pensylvanicus (DeGeer), and Bembidion quadrimaculatum L., comprising …

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Geostatistical Characterization Of The Spatial Distribution Of Adult Corn Rootworm (Coleoptera: Chrysomelidae) Emergence, M. M. Ellsbury, W. D. Woodson, S. A. Clay, D. D. Malo, J. Schumacher, D. Clay, C. G. Carlson Aug 1998

Geostatistical Characterization Of The Spatial Distribution Of Adult Corn Rootworm (Coleoptera: Chrysomelidae) Emergence, M. M. Ellsbury, W. D. Woodson, S. A. Clay, D. D. Malo, J. Schumacher, D. Clay, C. G. Carlson

Agronomy, Horticulture and Plant Science Faculty Publications

Geostatistical methods were used to characterize spatial variability in western ( Diabrotica virgifera virgifera LeConte) and northern ( Diabrotica barberi Smith & Lawrence) corn rootworm adult emergence patterns. Semivariograms were calculated for adult emergence density of corn rootworm populations in fields of continuous corn and rotated (corn/soybean) corn. Adult emergence densities were generally greater for northern corn rootworms than for western corn rootworms. The spatial structures of the adult rootworm emergence were aggregated as described by spherical spatial models for western corn rootworm and exponential models for northern corn rootworm. Range of spatial dependence varied from 180 to 550 m …

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Leafy Spurge Biological Control Using Black Dot Flea Beetles And Deleterious Rhizobacteria: Final Report Submitted To South Dakota Department Of Agriculture Weed And Pest Control, Sharon A. Clay, Mark A. Brinkman, Robert J. Kramer, Jan J. Jackson, Nels H. Granholm Apr 1998

Leafy Spurge Biological Control Using Black Dot Flea Beetles And Deleterious Rhizobacteria: Final Report Submitted To South Dakota Department Of Agriculture Weed And Pest Control, Sharon A. Clay, Mark A. Brinkman, Robert J. Kramer, Jan J. Jackson, Nels H. Granholm

Agronomy, Horticulture and Plant Science Faculty Publications

Size of leafy spurge (Euphorbia esula L) roots and their location in the soil profile are important factors relating to survival offirst-instar black dot flea beetle (Aphthona nigriscutis Foudras) larvae. First-instar larvae must find leafy spurge roots between 1 to 4 mm diam in the first 2 days after hatching from eggs for survival. In field studies, we ddermined that most flea beetle larvae reside within 7.6 em ofthe soil surface. Their location in the upper areas ofthe soil profile allows accessibility to desirable size roots, however the larvae are more susceptible to freezing temperatures in this region. Overall, there …

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Weed Seed Bank Emergence Across The Corn Belt, Frank Forcella, Robert G. Wilson, Jack Dekker, Robert J. Kramer, John Cardina, Randy L. Anderson, David Alm, Karen A. Renner, R. Gordon Harvey, Sharon Clay, Douglas D. Buhler Feb 1997

Weed Seed Bank Emergence Across The Corn Belt, Frank Forcella, Robert G. Wilson, Jack Dekker, Robert J. Kramer, John Cardina, Randy L. Anderson, David Alm, Karen A. Renner, R. Gordon Harvey, Sharon Clay, Douglas D. Buhler

Agronomy, Horticulture and Plant Science Faculty Publications

Field experiments, conducted from 1991 to 1994, generated information on weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of weed seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of …

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Leafy Spurge - A Review, Sharon A. Clay, Chad M. Scholes Jan 1997

Leafy Spurge - A Review, Sharon A. Clay, Chad M. Scholes

Agronomy, Horticulture and Plant Science Faculty Publications

Leafy spurge (Euphorbia esula L.) is a perennial herbaceous weed that infests millions of acres of range and pasture in the northern Great Plains. It outcompetes grasses and lowers land productivity because cattle will not graze infested areas even if spurge makes up only 10% of the vegetative biomass. This presentation will cover the history, taxonomy, and phenology of leafy spurge. A discussion of chemical, mechanical, and biocontrol techniques that aid in leafy spurge management will also be included.

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Analysis Of Spatial Distribution Of Canada Thistle (Cirsium Arvense) In Notill Soybean (Glycine Max), B. L. Broulik, J. Lems, S. A. Clay, D. E. Clay, M. M. Ellsbury Jan 1997

Analysis Of Spatial Distribution Of Canada Thistle (Cirsium Arvense) In Notill Soybean (Glycine Max), B. L. Broulik, J. Lems, S. A. Clay, D. E. Clay, M. M. Ellsbury

Agronomy, Horticulture and Plant Science Faculty Publications

The nonuniform spatial distribution of weeds across a field landscape complicates sampling and modeling, but allows site specific rather than broadcast management of weed populations. Where weeds are aggregated, densities measured at random locations are not independent, but rather spatially related or autocorrelated. Geostatistical methods were used to describe and map nonrandom distribution and variation of shoot density across ten well established patches of Canada thistle, a perennial weed, in a 65 hectare notillage soybean field in Moody county, South Dakota in 1996. Canada thistle densities were determined by counting the number of shoots present in a 20 by 50 …

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Atrazine And Alachlor Adsorption Characteristics To Benchmark Soil Series In Eastern South Dakota, Z. Liu, S. A. Clay, J. Gaffney, D. Malo Jan 1997

Atrazine And Alachlor Adsorption Characteristics To Benchmark Soil Series In Eastern South Dakota, Z. Liu, S. A. Clay, J. Gaffney, D. Malo

Agronomy, Horticulture and Plant Science Faculty Publications

Corn, grain sorghum, and soybean are grown on about six million acres in eastern South Dakota each year. Two herbicides used routinely for weed control are atrazine(6-chloro-N-ethyl-N’-(1-methylethyl)-1,3,5-triazine-2,4-diamine) in corn and grain sorghum and alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide) in all three crops. Six benchmark soil series that include a majority of the cropped acres treated with these herbicides are the Egan, Moody, Nora, and Brandt silty clay loams, and Clarno and Enet loams. Batch adsorption studies determined atrazine and alachlor binding characteristics to these soils and aids in assessing the amount of herbicide available for movement. These data also provide a basis for …

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Factors Affecting Atrazine Fate In North Central U.S. Soils, W. C. Koskinen, Sharon Clay Jan 1997

Factors Affecting Atrazine Fate In North Central U.S. Soils, W. C. Koskinen, Sharon Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Atrazine (6-chloro-N-ethyl-N′-(l-methylethyl)-l,3,5-triazine-2,4-diamine) is a herbicide of the triazine family used for controlling broadleaf and some grassy weeds in corn and sorghum. Since its introduction in the late 1950s, atrazine has been a popular herbicide because it is relatively inexpensive and, in most cases, gives good season-long weed control. It can be applied pre-or postemergence and is often tank mixed with grass herbicides, such as alachlor (2-chloro-N-(2,6-diethylphenyl-N-(methoxymethyl)acetamide), metolachlor(2-chloro-N-(2-2ethyl-6-methylphenyl)-N-(2-methoxy-l-methylethyl) acetamide), butylate (S-ethyl bis(2-methylpropyl)carbamothioate), or EPTC (S-ethyl dipropylcarbamothioate), or with other broadleaf herbicides, such as dicamba (3,6-dichloro-2-methoxybenzoic …

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Characterization Of Alachlor And Atrazine Desorption From Soils, Sharon A. Clay, William C. Koskinen Jan 1990

Characterization Of Alachlor And Atrazine Desorption From Soils, Sharon A. Clay, William C. Koskinen

Agronomy, Horticulture and Plant Science Faculty Publications

Herbicide desorption isotherms may be affected by the amount of nondesorbable herbicide present in soil. Nondesorbable alachlor (as determined after methanol extraction) generally increased on a Waukegan silt loam (Typic Hapludolls) and a Ves clay loam (Udic Haplustolls) during five 0.01 M CaCl₂ desorptions. Atrazine was totally extracted with methanol from the Waukegan soil after one desorption using 0.01 M CaCl₂. However, after five desorptions with 0.01 M CaCl₂ an average of 5.5 and 15.5% of the total recovered atrazine from two atrazine application rates was methanol nondesorbable from the Waukegan and Ves soils, respectively. Freundlich desorption isotherms adjusted for …

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