New Stinger herbicide label for apples
Stinger labeled for post-emergence weed control in established apples.
EPA has approved a Supplemental Label for use of Stinger (clopyralid, Dow AgroSciences, Indianapolis, IN) for post-emergence weed control in well-established, non-bearing and bearing apple trees. Stinger is effective against members of the Asteraceae family (composites), including heath aster, burdock, cocklebur, common groundsel, dandelion, goldenrod, horseweed, pineappleweed, sowthistle and Canada thistle. It is also active against all legumes, including alfalfa, birdsfoot trefoil, clovers and vetch. It also controls members of the nightshade family, including eastern black nightshade, hairy nightshade and groundcherry. It stunts horsenettle, smartweeds including prostrate knotweed and plantains. Stinger has virtually no activity against other herbaceous or woody plants.
Stinger is a hormonal herbicide that translocates throughout the plants. It can cause some curling and twisting of leaves and new shoots, so the label advises to avoid direct application to apple foliage, fruit or trunks. Slight contact with apple plants will not cause permanent crop injury. There is a 30-day preharvest interval.
Dr. Zandstra’s work is funded in part by MSU‘s AgBioResearch.