Efficiency of herbicide Terrsan, WDG depending on rates and application time against cow parsnip

Abstract

   Based on the results of done researches it is shown that the herbicide Terrsan, WDG (sulfometuron-methyl acid, 750 g/kg) application at the rate of 0,2–0,4 kg/ha considerably decreases the number and weight of cow parsnip (Heracleum Sosnowskyi Manden.) in 30 days after treatment for 62,2–81,6 % by number and for 89,1–95,6 % by weight; in 60 days – the plant dies fully. The maximum efficiency is reached while carrying out spraying before plants growing up or at their height of 20–30 cm (98,8–100 % kill), by application at cow parsnip (Heracleum Sosnowskyi Manden.) height 60–80 cm the efficiency is decreased up to 77,9 % by number and 97,4 % by weight. By the herbicide Terrsan, WDG application also the other plant components of phytocoenosis are dead.