(Wines&Vines) - Mealybugs took the rap last week when detection, transmission and management of leafroll disease were investigated at the Napa Valley Grapegrowers’ Vineyard Technical Group session about Sustainable Vineyard Practices, first of a series presented in cooperation with the UC Cooperative Extension. The session filled the Yountville Community Hall to capacity; even after extra chairs were added, many attendees had to stand to hear four hours of talks. The reason for the interest was clear: Leafroll virus is spreading very rapidly in Napa Valley