Quinclorac 75%DF 50%WP 25%SC Herbicide

Quinclorac is a hormone-type selective herbicide for barnyard grass in rice fields. It has prominent effectiveness in controlling barnyard grass at the 4 to 7 leaf stage, with one application capable of managing barnyard grass throughout the entire growth period of rice. Additionally, it can also control other weeds such as duck’s tongue and water celery. The recommended dosage is 13.3 to 26.7 grams per 100 square meters, applied in a spray. It is generally recommended to apply the herbicide after transplanting rice, when barnyard grass is at the 1 to 3.5 leaf stage.

Using quinclorac before the 2-leaf stage of rice can easily cause phytotoxicity, manifested as spreading leaves during the tillering stage, a lack of tillers, and the formation of onion-like leaves. Before the 3-leaf stage of rice, the maximum application rate should not exceed 25 grams of pure product per acre (equivalent to 50 grams of 50% Quinclorac wettable powder). Excessive use of Quinclorac, uneven spraying, or repeated applications may lead to phytotoxicity, characterized by deep green leaf color, slow tiller development, and onion-like leaves later on. In cases of mild phytotoxicity, seedlings may exhibit thickened, hardened, and brittle bases, with narrow and twisted heart leaves. Symptoms of phytotoxicity generally appear 10 to 15 days after application.