Study on the optimum herbicide application time for control of curly dock (Rumex crispus L. ) in grazing pasture

摘要

This experiment was conducted for three years to find the optimum herbicide application time for control of the exotic and broad-leaf weed, curly dock (Rumex crispus. L). in grazing pastures of the Animal Genetic Resources Station. NLRI. The botanical composition of the experimental field consisted of grass 59%. curly dock 37. 7% . and others 3. 3%. A broad-leaf herbicide was applied at four different stages (stalking stage (control). 3 days, 10 days and 20 days after cutting). The control efficiency on curly dock at the stalking stage was 91% and was 92, 99 and 99%, at 3, 10, and 20 days after cutting respectively. The seed of curly dock germinated 5-15 days after cutting. According to these results, application 20 days after cutting was the most effective method of curly dock control in the grazing pasture.