2019 年 25 巻 p. 629-634
River levee, controlled by country, is covered with turf, Zoysia Japonica, after construction. That turf is managed by, manual root extraction, weeding, and fertilization (3, 2, 1time/year each) for first three years. After the fourth year, weeding and grass gathering is implemented (2, 1time/year each) However, under this vegetation management, due to the lack of labor for root extraction workers and invasion of the plant which declines turf early, the levee turf cannot be maintained properly. It causes deterioration of visibility at levee patrol and inspection and increase the disposal cost of cutting grass. In the previous report, we focused on plant growth regulators and herbicides to address these issues, and obtain certain effects conducted by one-year field experiment. In this paper, based on the results, we clarified the effect of using the herbicides over two years.
