Three mechanical weed control techniques in spring cereals

An inter-row hoe suitable for cereals was developed for the study, and fiel d experiments were conducted to compare inter-row hoeing with weed harrowin g, rotary hoeing and chemical control. The treatments were performed once d uring the growing season. Inter-row hoeing was studied at row spacings of 1 80 mm and 250 mm. The weeding effect of the different methods was measured by weighing the we eds remaining just before harvesting. Inter-row hoeing was the most effecti ve of the mechanical methods. Weed harrowing was as good as hoeing in silty clay soil but less effective in mull soil. Rotary hoeing was the least eff ective. Herbicide spraying was more effective than the mechanical methods i n both soils. Increasing the spacing between rows from the standard 125 mm to 250 mm decr eased the yield of barley by 12-13%. Inter-row hoeing affected the yield ve ry 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%. Alt hough inter-row hoeing seems to be a fairly effective method for weed contr ol, it may be difficult to compensate for the yield loss due to the increas e in row spacing.