As Rely 280 from Bayer CropScience comes off patent, several other glufosinate products are entering the market.
Rely has been recommended as a post-emergence herbicide in grapes for years. But the herbicide has not been recommended for use on peaches or apples.
The newcomers to the market have not only grapes on their labels, but also stone fruit, pome fruit, blueberries and other crops, according to a Rutgers University grower newsletter. Among those products are Cheetah.
Although Rutgers researchers have never evaluated Rely 280 on blueberries, they have not recommended it because of potential injury.
In trials conducted on peach and apple trees, glufosinate was absorbed through the mature brown park of the lower trucks of trees. It killed the cambium layer of the bark where the herbicide contacted the bark.
Applications were made in late spring using typical rates and application methods.
No injury was observed during the year of application but the following year.
The herbicide doesn't cause injury all the time. But when it does, it can be devastating.
Roundup, 2,4-D and Stinger were included in the studies and did not cause injury.
Glufosinate should not be confused with glyphosate, which is marked as Roundup and a host of other brand names.
Based on the trial results, Rutgers University Extension specialist will continue to recommend Rely 280 and other glufosinate products for grapes but not for stone fruit or pome fruit.