Inter-row and intra-row weed control with a hoe-ridger

Abstract

Inter-row and intra-row weed control by a hoe-ridger, as influenced by soil type, plant height, working depth, tool position and the weather after cultivation, were investigated in the laboratory by means of a model experiment. In the path of the hoe, weeds were uprooted; 57% were killed by incorporation in the soil and 33% by desiccation on the surface. Wetting after cultivation decreased the number of weeds killed to a total of 78% instead of 90%. Alongside the hoe path, in a band of width 15–20 cm, 45% of the weeds were killed by being covered with soil loosened in the path of the hoe. A soil cover of 1·5 cm was found to be lethal for small weeds, and 2 cm was lethal for longer ones, in a band of width 5–10 cm alongside the hoe path. The width of this band could be increased by a slight backward tilting of the rake angle of the hoe. On sandy soil, 34% fewer weeds were killed than on loamy soil owing to the larger quantity of roots in the soil transported sideways. Increasing the working depth from 2·5 cm to 4·0cm gave only a small increase (less than 10%) in the number of weeds killed.