Three mechanical weed control techniques in spring cereals

Abstract

An inler-row hoe suitable for cereals was developed for the study, and field experiments were con-ducted to compare inter-row hoeing with weed harrowing, rotary hoeing and chemical control. The treatments were performed once during the growing season. Inter-row hoeing was studied at row spacing» of 180 mm and 250 mm. The weeding, effect of the different methods was measured by weighing the weeds remaining just before harvesting. Inter-row hoeing was the most effective of the mechanical methods. Weed harrow-ing was as good as hoeing in silty clay soil but less effective in mull soil. Rotary hoeing was the least effective. Herbicide spraying was more effective than the mechanical methods in both soils. Increasing the spacing between rows from the standard 125 mm to 250 mm decreased the yield of barley by 12-13%. Inter-row hoeing affected the yield very slightly. The yield decreasing was lower at a row spacing of 180 mm than at 250 mm. Weed harrowing and rotary hoeing decreased the yield 5-10%. Although inter-row hoeing seems to be a fairly effective method for weed control, it may be difficult to compensate for the yield loss due to the increase in row spacing.