Evaluation of acetolactate synthase/acetohydroxyacid synthase – inhibiting herbicide spot applications and mesotrione tank mixtures for narrow-leaved goldenrod management in lowbush blueberry

Narrow-leaved goldenrod is a common creeping herbaceous perennial weed in lowbush blueberry that is difficult to manage due to limited control from pre-emergence hexazinone applications and incomplete control from post-emergence mesotrione applications. The objectives of this research were to (1) evaluate a range of summer and fall non-bearing year acetolactate synthase/ acetohydroxyacid synthase (ALS/AHAS) – inhibiting herbicide spot applications for narrow-leaved goldenrod control, and (2) evaluate broadcast applications of mesotrione applied alone or in tank mixture with foramsulfuron, nicosulfuron + rimsulfuron, flazasulfuron, and clopyralid for crop tolerance and management of narrow-leaved goldenrod in lowbush blueberry. Summer non-bearing year spot applications of glyphosate and flazasulfuron caused >90% visual injury to narrow-leaved goldenrod and reduced both non-bearing and bearing year shoot density. Spot applications of tribenuron methyl, foramsulfuron, nicosulfuron + rimsulfuron, halosulfuron, and pyroxsulam caused variable injury and did not consistently reduce narrow-leaved goldenrod shoot density. Results were similar in the fall non-bearing year experiment and they indicate that flazasulfuron could be used as an alternative to glyphosate for spot applications to narrow-leaved goldenrod due to lower crop injury from this herbicide relative to glyphosate. Broadcast mesotrione applications injured narrow-leaved goldenrod but did not reduce shoot density. Broadcast foramsulfuron, nicosulfuron + rimsulfuron, and clopyralid applications caused 60% visual injury to narrow-leaved goldenrod and reduced non-bearing year and bearing year shoot density. Flazasulfuron efficacy was reduced when applied in tank mixture with mesotrione.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author