Many farmers believe that tillage also helps reduce disease problems. However, research has shown that there is actually less disease problems under direct seeding as compared to conventionally tilled systems. For weed control, there often is a mistrust of relying solely on herbicides by many farmers which also helps justify conventional tillage practices. However, poor weed control using tillage under wet or very moist soil conditions is not uncommon and is very often not given the same criticism. In addition, under low disturbance direct seeding, some factors are generally not acknowledged by those considering changing to this system.
Many weeds rely on mechanical disturbance in order to germinate.
Wild oats is another major problem weed that tillage promotes its growth. The narrowing of the depth of the seed bank will also allow the zero-incorporated granular herbicides to be most effective. Crop rotation is often an overlooked aspect of weed control. For direct seeding to be truly effective and profitable, the cropping rotation needs to be expanded from only cereals. Research indicates that a continuous cereal rotation is the least economic rotation.