Creeping Bellflower Response to Glyphosate and Synthetic Auxin Herbicides

摘要

Creeping bellflower (Campanula rapunculoides) is a difficult to manage weed commonly found in turfgrass and residential areas. We evaluated the efficacy of selected postemergence herbicides (glyphosate, dicamba, clopyralid, quinclorac, and triclopyr) on greenhouse-grown creeping bellflower. The experiment was conducted in Jan. 2016 and repeated in Sept. 2016. Each herbicide was applied at five rates plus a nontreated control. Clopyralid caused greater creeping bellflower biomass reduction and mortality than the other herbicides investigated. The herbicide dose required to cause 50% mortality was lowest for clopyralid [86-138 g.ha(-1) acid equivalent (a.e.)] compared with dicamba (221-536 g.ha(-1) a.e.), glyphosate (196-678 g.ha(-1) a.e.), triclopyr (236-782 g.ha(-1) a.e.), and quinclorac (&3000 g.ha(-1) a.e.). Clopyralid could be an effective herbicide for managing creeping bellflower, although it is currently not registered for use in many habitats where this plant is a problematic weed.