PROBLEM TO BE SOLVED: To simultaneously implement a wide-range weeding function of a ridge and an earthing-up function sufficient for forming the ridge.SOLUTION: A working member to be connected to a support member of a middle-bone beam of a cultivator unit body includes a weeding-cum-earthing-up plate on the lower part of the support tool connected to the support member, the weeding-cum-earthing-up plate extending from a furrow to crop root edges, and dragged along the ridge, where a lower end edge side in the longitudinal direction is formed into a substantially linear plate or a brush acting surface. The working member is connected to the middle-bone beam of the cultivator body via an automatic vertical-position adjusting device using a parallel link.SELECTED DRAWING: Figure 3
