Abstract
A unique depth control system regulated by independent furrow openers was designed and developed for zero tillage systems. The appropriate furrow opener for the control system was investigated on soft, medium, and hard soils. Three furrow openers (hoe, tine and 2-disc) were evaluated based on furrow shape consistency, lateral and vertical seed distribution, soil penetration and disturbance. Results showed that the hoe furrow opener showed no significant difference in furrow shape even in hard soils with great soil penetration, and the variation of the lateral and vertical seed distributions was reasonable. Thus, the hoe furrow opener was selected for the control system.
