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South Dakota State University

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Articles 271 - 281 of 281

Full-Text Articles in Life Sciences

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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Food Habits And Diet Overlap Of Age-1 And Older Walleye And White Bass In Lake Poinsett, South Dakota, Andrew B. Starostka Jan 1999

Food Habits And Diet Overlap Of Age-1 And Older Walleye And White Bass In Lake Poinsett, South Dakota, Andrew B. Starostka

Electronic Theses and Dissertations

White bass Marone chysops and walleye Stizostedion vitreum coexist in several of the large glacial lakes in eastern South Dakota. I collected age-1 and older white bass and walleye in Lake Poinsett, South Dakota during May, July and September, 1998 to determine food habits and diet overlap using percent by weight to describe diets and Schoener's index (Cxy) to determine diet overlap. Macroinvertebrates were common prey items for white bass in all length groups during all sample dates. The primary macroinvertebrates consumed by white bass were corixids, amphipods and dipterans. Fish, as a group, were second in diet importance over …

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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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Eastern South Dakota Wetlands, Rex R. Johnson, Kenneth F. Higgins, Michael L. Kjellsen, Charles R. Elliot Jan 1997

Eastern South Dakota Wetlands, Rex R. Johnson, Kenneth F. Higgins, Michael L. Kjellsen, Charles R. Elliot

Natural Resource Management Faculty Books

Diverse and extensive wetland resources have always been familiar parts of the landscape to farmers, hunters, and residents of eastern South Dakota. The journals and oral histories of adventurers, trappers, and natives and immigrants reveal how wetlands shaped the wildlife and the people who lived on and modified the land to meet their own needs. The history of South Dakota wetlands parallels the history and interactions of people and wetlands elsewhere in North America and the world. This interaction can best be characterized as constant conflict. Driven primarily by economics, farmers the world over expended tremendous energy to "reclaim" and …

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Wetland Resources Of Eastern South Dakota, Rex R. Johnson, Kenneth F. Higgins Jan 1997

Wetland Resources Of Eastern South Dakota, Rex R. Johnson, Kenneth F. Higgins

Natural Resource Management Faculty Books

The mere mention of the word "wetland" in coffee shops and other gathering places on the prairies today brings out emotions and opinions that run the gamut from saving them all to draining them all. To some people, what we do with wetlands has been, and still is, a personal choice, a matter of exercising individual rights on private property. To others, wetlands are community resources that provide values that touch all of society. They contend that what is done to and about wetlands is a community decision regardless of ownership. Herein lies the controversy we have experienced over wetlands …

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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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Population Status And Characteristics Of Macrhybopsis Gelida, Platygobio Gracilis And Rhinichthys Cataractae In The Missouri River Basin, Selena J. Werdon Jan 1992

Population Status And Characteristics Of Macrhybopsis Gelida, Platygobio Gracilis And Rhinichthys Cataractae In The Missouri River Basin, Selena J. Werdon

Electronic Theses and Dissertations

Few sturgeon chub (Macrhybopsis gelida: Cyprinidae) have been collected in the last decade, therefore their status, habitat selection and morphology were investigated at 172 previous collection sites. Data on two ecologically similar species, Platygobio gracilis and Rhinichthys cataractae, were also collected. Macrhvbopsis gelida were collected at 28 sites on the Powder River (n = 158) in Wyoming and Montana, and at one site on the Yellowstone River (n = 1) in Montana. Age-I, Age-II and Age-III M. gelida were collected. Specimens were 37 to 95 mm in total length. Macrhvbopsis gelida were ripe in mid-June, at water temperatures of 18.3-22. …

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Historical Crop / Climate Relationships In South Dakota, D.G. Kenefick, J.C. Harlan, K.K. Weischedel, P.D. Evenson Jan 1984

Historical Crop / Climate Relationships In South Dakota, D.G. Kenefick, J.C. Harlan, K.K. Weischedel, P.D. Evenson

Agronomy, Horticulture, and Plant Science Publications

Crop performance and climatic records were collated for high production counties in South Dakota to evaluate the effects of temperature and precipitation on yields. The crops involved were corn, soybeans, sorghum, oats, spring wheat, and winter wheat. Records were compared for the period from 1965 to 1982. The computer data file for each county includes seven climatic parameters, dates of plant development, adjusted yield-and yield rank by year. The crop/climate record for the 17-year period was evaluated in sixteen counties per crop each year. Thus, 272 county x year observations were made for each crop, except for soybeans which involved …

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Separation Of The Selenium Compounds In Seleniferous Plant Protein Hydrolysates By Paper Partition Chromatography, Arnold L. Smith Jan 1949

Separation Of The Selenium Compounds In Seleniferous Plant Protein Hydrolysates By Paper Partition Chromatography, Arnold L. Smith

Electronic Theses and Dissertations

In 1943 Franke reported that the protein of "allolied" or "toxic" wheat carried the toxicant, and Franke and Painter in 1935 reported that those "toxic" proteins contained selenium which was in organic combination in the protein. There has been much speculation regarding the possibility of selenium replacing sulfur in the amino acids cysteine and methionine. The toxicity of selenium in selenium analogs of these compounds is similar to that of selenium occurring naturally in proteins seleniferous cereals, which indicated that the selenium may be present in the proteins as the analogue of these sulfur amino acids.

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The Effect Of Cultivation On Certain Chemical And Physical Properties Of Some South Dakota Soils, Oscar E. Olson Jan 1937

The Effect Of Cultivation On Certain Chemical And Physical Properties Of Some South Dakota Soils, Oscar E. Olson

Electronic Theses and Dissertations

Soil Nutrient losses have followed closely in the paths of advancing frontiers in agriculture. Remedies for depletion as the result of overcropping were sought by George Washington, whose interest and investigation of soil nutrient losses probably represent the earliest attention given to land exploitation in the United States, which at the present time has become a problem of national concern. Soil losses have been attributed to a number of causes , among which are cropping, erosion, leaching, burning, and rapid oxidation of organic matter in the soil. Associated with soil nutrient losses, certain significant physical and chemical changes may occur …

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