Marestail, also known as horseweed or Canada fleabane, is a winter or summer annual weed in Nebraska. Historically, marestail was found in waste area, field edges, along roadsides, and railway tracks; however, no-till crop production systems over the last 20 years favor marestail germination and establishment in agronomic crops in Nebraska.
In Nebraska, eight weed species (common ragweed, common waterhemp, giant ragweed, kochia, marestail, Palmer amaranth, redroot pigweed, and shattercane) have been confirmed resistant to at least one herbicide. Six of them — common ragweed, common waterhemp, giant ragweed, kochia, marestail, and Palmer amaranth — have been confirmed resistant to glyphosate in Nebraska. This article reviews information presented at the Weed Management Field Day at the UNL South Central Ag Lab, focusing on field demonstrations and methods to reduce the development of further herbicide resistance.
As growers look for new opportunities to rotate herbicide active ingredients, combination herbicides may offer the benefits they're looking for. Acuron™ is a combination of four herbicide active ingredients: atrazine (10.93%), bicyclopyrone (0.65%), mesotrione (2.6%), and S-metolachlor (23.4%) plus the safener benoxacor. Acruron may be used pre-emergence and post-emergence in field corn, seed corn, and silage corn. Acuron may also be used in sweet corn and yellow popcorn, but the application must be made prior to crop emergence or serious crop injury may occur.