Brian Bahder transfers a first-instar grape mealybug from a grapevine leafroll-diseased Concord vine to a healthy Concord vine to assess mealybug competency as a vector. Melissa Hansen With the insidious spread of grapevine leafroll disease in Washington State vineyards, Washington State University scientists have worked to help growers better detect and control grape mealybug, a known vector of the disease. WSU recently developed trapping density recommendations for a new pheromone-based trap that will alert growers when mealybugs become active in the spring. Improved monitoring of grape mealybug in vineyards may help growers take action at the proper time to control […]