Conventional- and no-tillage effects on upper root zone soil conditions

One major objective of tillage is to loosen a soil and, thereby, create an improved soil condition for water infiltration, crop establishment, and plant growth. This implies that where tillage is not performed, as with no-tillage, soil conditions might be inferior to those of a tilled soil. However, no major adverse effects of no-tillage on soil conditions have been noted in the semiarid region of Texas. Also, crop yields on dryland have been favorable. This study was conducted to determine the effects of conventional- and no-tillage crop production methods on water retention, organic matter concentration, mean weight diameter of water-stable aggregates, bulk density, and penetrometer resistance of Pullman clay loam (Torrertic Paleustoll) at Bushland, Texas. These factors were significantly affected, but there was no consistent advantage or disadvantage for either tillage method. Wheat (Triticum aestivum L.) and grain sorghum (Sorghum bicolor (L.) Moench) yields have been favorable in the dryland rotation fields that were sampled for the soil measurements. Grain sorghum yielded 5.10 Mg ha^?1 of grain with conventional tillage and an average of 5.32 Mg ha^?1 of grain with no-tillage in 1987, the year in which the soil conditions were evaluated. The favorable yields indicate that no-tillage management does not adversely affect any of the measured Pullman (Torrertic Paleustoll) soil physical conditions to the point that crop yields are adversely affected.