Herbicide resistance a growing concern

Grapegrowers tend to base weed control choices on what they used successfully in the year of their best yields. They may vary those choices somewhat to account for specific problems their scouts turn up, but usually there are two or three compounds they use year after year. Instead of finding contin-ued success and high yields, those “tried-and-true” weed control compounds are bringing two other things to vineyards: herbicide-resistant and herbicide-tolerant weeds.