Wheel Traffic Placement Effects on Corn Response under No-Tillage and Conventional Tillage

Abstract

Although previous studies on the Del-Mar-Va peninsula have indicated that vehicular wheel traffic from small scale farm equipment (<5 tons/axle) does not result in soil conditions considered detrimental to plant growth under no-tillage (NT) and conventional tillage (CT) management, farmers are still concerned that decreased plant response and reduced crop yields may result. A study was conducted from 1988 to 1991 to evaluate the effects of wheel traffic placement on corn (Zea mays L.) growth, nutrient uptake, and yield response under NT and CT. The soil was a Bertie silt loam (fine, loamy, mixed, mesic Aquic Hapludult) and was somewhat poorly drained. Replicated field plots were established for NT and CT corn in which rows of corn were subjected to different wheel traffic patterns. The patterns were : wheel traffic on neither side of the row (NS), wheel traffic on one side of the row (1S), wheel traffic on both sides of the row (2S), and wheel traffic on both sides and in the center of the row (IR). Corn plant emergence, biomass production, nutrient uptake, and yield were evaluated. The results generally indicated that NT had higher emergence rates than CT each year of the study. The NT plots also generally exhibited higher N and P levels for all growth components than the CT. In the grain tissue, NT plots had higher K levels than CT. Wheel traffic had significant effects on plant emergence 3 out of 4 yr. Wheel traffic did not have significant effects on biomass production and yield in 1988 or 1989, but did in 1990 and 1991. The IR treatment consistently exhibited reduced plant growth and yield response. It is felt that the concerns commonly expressed by farmers on the detrimental effects of wheel traffic activity may be due to plant responses observed in the end rows on the field boundaries. These end rows are exposed to wheel traffic directly in the row during planting operations. As long as small scale farm equipment is used and the soil is worked at proper moisture contents, there does not seem to be strong justification for regular deep-tillage of Del-Mar-Va's coastal plain soils to overcome perceived problems related to vehicular wheel traffic activity on continuous NT and CT fields.