ABSTRACT
Changes in physical properties and responses of roots due to tillage are markedly dependent on the soil type, plant species, stage of crop development, and weather and climate conditions. Tillage is the most obvious way to modify soil structure deleterious to the root growth. Numerous studies have been conducted on root growth and distribution as affected by reduced tillage compared to conventional tillage. J. W. Bauder et al. evaluated the effects of various tillage systems with confined wheel traffic patterns on com root growth and found that although vehicular traffic affected the extent of root development and distribution, the type of tillage used had a much greater effect on overall root length and root distribution. Soil layers that may restrict root growth are plowpans, fragipans, duripans, fine-textured B-horizons, claypans, and high clay horizons. The depth and thickness of the pans depend on site conditions.
