Effect of Preplant Wheel Traffic on Soil Compaction, Water Use, and Growth of Spring Wheat

Abstract

AbstractThe effects of wheel traffic on small grain emergence and early growth is commonly observed in production fields. However, the plant response is not consistent, but appears dependent on soil and climatic conditions. The objective of this study was to measure the effects of preplanting wheel traffic on soil compaction and ‘Era’ spring wheat (Triticum aestivum L.) growth in field plots in West Central Minnesota under a range of growing season conditions. The 1975 and 1977 growing season were slightly wetter than normal while the 1976 growing season was significantly drier. Treatment comparisons were wheat planted in soil compacted by wheel traffic during spring field operations and wheat planted in soil that had not been wheel trafficked. Normal field‐sized equipment (tractor weight ranged from 4000 to 7000 kg) was used to perform spring fertilizer application, spring tillage, and seeding. The controlled wheel traffic concept was used. In 1975, wheat emergence in the wheel‐tracked soil was delayed by about 10 d because of poor seed‐soil contact, and grain yield was 27% lower than in the nontracked soil. Shortly after planting in 1976, the nontracked soil lost excessive amounts of water by evaporation from the loose 0‐ to 0.15‐m layer. As a result, wheat growth in the wheel‐tracked soil was better than in the nontracked soil, and yield was increased by 53%. In both 1975 and 1976, there was slightly more water used from the wheel‐tracked treatment than from the nontracked treatment, resulting in differences in water use efficiency. Effects of wheel traffic on wheat growth and yield were closely related to growing season precipitation and illustrate the need to consider probable climatic conditions when developing management systems for controlling field vehicular wheel traffic.