Daane, K.M., Weber, E.A., & Bentley, W. 2004 Vine Mealybug: Formidable pest spreading through California vineyards.. Practical Winery & Vineyard Magazine May/June 2004.

Notes: Several species of mealybugs are pests of grapevines in many parts of the world. In California, the grape mealybug, long-tailed mealybug, and obscure mealybug have long been present in vineyards, but they are usually minor pests not requiring chemical control. Recently, the invasive vine mealybug (VMB) has emerged as a serious pest in many parts of the state. It brings with it the need for aggressive chemical management. Vine mealybug is found in the Mediterranean regions of Europe and North and South Africa, as well as grapegrowing regions in the Middle East, Argentina and Mexico - and now in California.In California, vine mealybug was first discovered in 1994 in table grape vineyards in the Coachella Valley (Riverside County), although it probably entered the state a year or two earlier. It spread throughout the Coachella Valley, and in 1998 was found in the southern San Joaquin Valley (Kern County). Its dispersion into new regions has been dramatic: VMB was found in Fresno County in 1998, Santa Barbara County in 2000, San Luis Obispo County in 2001, and in El Dorado, Madera, Monterey, Napa, Sacramento, Sonoma, and Stanislaus counties in 2002. To date (March 2004), VMB has been found in 17 counties in California (Table I). It is likely that there are more infestations that have yet to be identified or have not been reported.Circumstantial evidence suggests this rapid dispersion resulted from movement of infested vineyard equipment (mechanical harvesters, bins, tractors, etc.) and through sales of infested nursery stock (from 1998 to 2003). Other possible factors include spread with field crews and natural dispersion (such as birds and wind-blown infested leaves).