Background Infomation

Vine Mealybug (Planococcus ficus) is a serious pest of North Coast Vineyards.  Vine Mealybug (VMB) was first discovered in California's Coachella Valley in 1994.  By 1998 it was found in southern San Joaquin Valley vineyards and has continued to spread north.  By 2002 the first infestations were found in Carneros vineyards.  As of the 2006 growing season there have been around 50 confirmed infested sites in Napa County. 

Unlike the "Grape Mealybug Complex"--Grape and Obscure species (Psuedococcus spp.), Vine Mealybug has several generations (3-7) per season and can live and feed on all parts of the vine, from roots to upper canopy.  All lifestages are found throughout the year on the vines.They are cryptic insects and hide under bark making them especially difficult to detect until their populations are large enough to cause damage to the fruit.  The female insect lives on the vine and will cause economic damage to the crop.  The male insect is effectively microscopic and must lured with a pheromone trap and the trap read under a microscope by someone trained in their identification.  Vineyard crew training is essential in their detection and control of the female VMB. 

Some signs to look for:

• "wet-looking" trunks and bark, peel back the bark to inspect for VMB
• Argentine ants, follow the trail to observe what they are tending
• honeydew and/or sooty mold

All mealybugs excrete a sticky substance known as "honeydew".  Argentine ants (Linepethema humile), and some other sugar-feeding ants, protect mealybugs from predators so that they can harvest the honeydew.  This makes it especially difficult for natural predators to control mealybugs.  For more effective control by natural predators, ant control is essential.  VMB produces a prolific amount of honeydow.  Sooty mold can grow on the honeydew causing econonic damage to the crop.  In addition to crop damage, many species of mealybugs have been found to be a vector for some of the Grapevine Leafroll Associated Viruses (GLRaV).

What you can do

• Actively scout your vineyards starting in spring looking for crawlers and overwintering adults (female).
• Hang pheromone traps beginning in June to trap male VMB.  This will give you an idea if there is an infestation nearby.  The infestation may be in your vineyard, or a neighboring vineyard some distance away.
• Participate in the Vine Mealybug Workgroup, monthly meetings and trapping program.
• Train your vineyard crew to look for signs of VMB and to learn to identify female VMB.