Rototilling and mowing between rows and hand weeding within rows were still the best weed control strategies for the vineyard, according to Miles and Miller.

The Wonder Weeder provided good in-row weed management, but it may also cause significant damage to first-year vines, whose thinner trunks can't withstand the cultivator's tripping mechanism. Miller noted that the Wonder Weeder would probably work better when the vineyard's plants are mature, with thicker trunks and well established root systems.

Others participating on the weed management study were research associate Jonathan Roozen and technical assistant Jacqueline King, both from WSU Mount Vernon NWREC, and Mercy Olmstead, assistant professor of ag-horticultural sciences at the University of Florida in Gainesville.

New studies of fungicides, freezing

Starting this year, Miles and her colleagues are fielding two more studies on organic wine grapes. The first, being conducted at a commercial vineyard, will evaluate the cost effectiveness of four newer organic fungicides for control of grape powdery mildew.

The second will explore whether replanting or retraining is a better recovery method in a severely injured young vineyard after freezing, an apt trial considering that the Mount Vernon vineyard lost 30 percent of its plants due to freezing last November.

Learn more about WSU's west side research and Extension by visiting