Southwest wheat growers are finding an increasing problem with herbicide resistant ryegrass. The herbicides that have controlled ryegrass in the past are showing a failure to control some ryegrass in wheat stands, according to industry representatives and Texas AgriLife Extension specialists.

The herbicide failures are growing every year. Jim Swart, Texas AgriLife Extension integrated pest management specialist, estimated that 10 percent of the wheat in northeast Texas showed resistant ryegrass infestations, reported Western Farm Press. “I think that’s closer to 20 percent this year,” he said.

Tony Driver, a tech representative for Syngenta, manufacturer of Axial XL, said the problem seems fairly localized “but must be taken seriously. This can be a serious problem if we don’t address it.”

To manage the situation, Swart recommends a two-step program. Western Farm Press reported, that the program calls for application of Axiom, a Bayer CropScience herbicide, at 6 ounces per acre when you can “row your wheat. We don’t want to apply until wheat is up to stand, as Axiom has some preemergence activity,” Swart said. Following that, Axial XL is applied at 16.4 ounces per acre at the two-leaf stage of ryegrass, usually in early to mid January. “We add a half-ounce of Amber with Axial XL to control broadleaf weeds,” he said.

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