Ohio grain farmers are likely to find more glyphosate-resistant marestail in their fields this year because of the wet fall and warm winter, says an Ohio State University Extension weed specialist.
Marestail is the most abundant, herbicide-resistant weed Ohio growers deal with, and according to Mark Loux, a combination of herbicide applications can provide the most consistent, effective control.
Resistant populations were traditionally found in southwestern Ohio, but now essentially all of the marestail statewide is glyphosate-resistant. Twenty-five percent of marestail also is resistant to ALS inhibitors, meaning postemergence herbicide applications are often the least effective, Loux said.
“The situation takes on even more significance this spring as crop growers were hampered from fall applications due to the lack of time and good weather last fall to get herbicide applied,” he said.
Loux offers several approaches growers can take to deal with increasingly difficult weed control scenarios:
* Apply burndown plus residual herbicides in late March or early April, which is applying early enough that burndown of emerged crops is not an issue.… Continue readingRead More »