ROOT GROWTH AND SOIL STRENGTH IN CONSERVATION AND CONVENTIONAL TILL COTTON

Authors: Busscher, Warren; Bauer, Philip

Submitted to: Southern Conservation Tillage for Sustainable Agriculture Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 6/24/2002
Publication Date: 6/24/2002
Citation: BUSSCHER, W.J., BAUER, P.J. ROOT GROWTH AND SOIL STRENGTH IN CONSERVATION AND CONVENTIONAL TILL COTTON. CD-ROM. SOUTHERN CONSERVATION TILLAGE FOR SUSTAINABLE AGRICULTURE PROCEEDINGS. 2002. P. 300-304.

Interpretive Summary:

Technical Abstract: Corn (Zea mays L.), soybean [Glycine max L. Merr.], and wheat (Triticum aestivum L.) have shown inverse linear relationships between average soil strength within the top 2 feet of the profile and yield in Coastal Plain soils that have subsurface hard layers. We tested this relationship for cotton (Gossypium hirsutum L.) hypothesizing that root growth and lint yield of cotton would be greater with annual deep tillage. Effects of surface tillage, deep tillage, and rye (Secale cereale L.) cover crop were evaluated. Reduction of root growth was correlated (r**2 = 0.66 to 0.68) with mean soil strength or with the 95th percentile of soil strength distribution, which acted as a stabilized, surrogate measurement of maximum strength that cotton roots would encounter. Cotton lint yield was not reduced by the treatments, even though root growth decreased with increasing soil strength. Lack of tillage treatment effects on yield may have been the result of management practices that employed a small disk in conventionally treated plots and maintained traffic lanes in all plots. Both of these practices would help prevent re-compaction. These management practices may help reduce the frequency of subsoiling while maintaining viable production practices for cotton grown in traditionally wide (38-in) rows.