Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Plant Science


The addition of crop oils to post-emergent applications of atrazine has enhanced the weed control properties of the atrazine. This treatment has been used very effectively for the control of annual weeds in corn and sorghum. Because the treatment was applied post-emergence, it could be empl6yed after the farmer found he would have difficulty controlling annual weeds. The treatment was, then, an ideal salvage measure for the farmer who could not cultivate his field because of rainy weather. The atrazine plus oil treatment appeared to work better under rainy weather conditions than it did A rainy season in the southeastern part of South Dakota in 1967 caused many farmers to turn to atrazine plus oil to control the annual weeds they could not cultivate out of their corn and sorghum fields. Many farmers who used the atrazine plus oil treatment had satisfactory weed control and received no apparent injury to their crops. In other instances, sorghum fields sprayed with atrazine plus oil were severely injured. Most of this injury was confined to stunting and delay in maturity . Because of such erratic results, a survey was conduct ed by Parker and Stritzke to determine the extent of the injury and to study the type of weather conditions prior to and immediately following spraying. It appeared that the most severe injury was preceded by at least three days of cool weather when temperatures were less than seventy degrees Fahrenheit. The injury to the sorghum raised questions about the effects of atrazine and its carriers to the sorghum plant. A study was initiated to measure the physiological responses of the sorghum plant and to note the gross physical responses of the plant in height, weight and grain yield.

Library of Congress Subject Headings


Weeds -- control



Number of Pages



South Dakota State University