Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Plant Science

First Advisor

W. E. Arnold


In recent years, farmers have made dramatic changes in their tillage practices. The conventional plow-disk-drag system allows farmers to control weeds, remove crop residue, and prepare the soil for planting. The development of 2,4-D [(2,4-dichlorophenoxy) acetic acid] in the 1940’s and of additional herbicides since then has greatly reduced the need for tillage to control weeds. Improvements in planting equipment allow farmers to use crop residue to their benefit. Farmers using tillage systems which leave residue on the soil surface can realize savings of time, labor, and equipment together with increased moisture and soil conservation while. maintaining yields equal to conventional tillage. As tillage is decreased, several potential problems become apparent. Incorporation of fertilizer becomes more difficult nitrogen requirements may increase. Soil is slower to warm in the spring end may become more compacted without tillage to loosen the soil. Weed pressure may increase and weed species may change which reduced tillage. Crop residue can intercept herbicides applied and methods of herbicide application may have to be changed for optimum control. Crop diseases and insects may become more troublesome. An evaluation of potential benefits and problems associated with reduced tillage systems in southeastern South Dakota would be beneficial to farmers. The objectives of this research were to determine (1) whether presently available herbicides can effectively control weeds in reduced tillage systems planted in a corn-bean rotation, (2) the effect of reduced tillage systems on residual soil fertility and other soil properties, and (3) the potential for weed species shifts with reduced tillage systems in southeastern South Dakota.

Library of Congress Subject Headings

Conservation tillage
Weeds -- Control
Conservation tillage -- South Dakota
Weeds -- Control -- South Dakota
Soils -- South Dakota
Weeds -- South Dakota



Number of Pages



South Dakota State University


No Copyright - United State