Eggs hatch in 1-2 weeks and larvae drop to the ground, enter the soil, and feed on grape roots until cold weather. Larvae consume smaller roots and eat pits into larger ones. This damage is much more important than the adult foliar injury. Vines become unthrifty, reducing yield, and may even die after several years of infestation. If vines are planted in soil poorly suited to grape, any damage by grape rootworm will have a more severe effect. The life cycle takes one to two years for completion. A related species, F. longipes (Melsheimer), the southern grape rootworm, has been found to be more common than F. viticida in North Carolina. Its distribution in Virginia is not known.

Chemical control is directed toward adults soon after emergence, before oviposition. First and second grape berry moth sprays may control grape rootworm. Timing is important.  If sprays are applied too early, many adults may still be in the soil, and spray residues may not last long enough to give control during the whole adult feeding period.  If applied too late, eggs will already have been laid under loose bark, providing for the next generation of root reeders.  Pupae may be destroyed by intensive shallow cultivation of soil until adults emerge in late June.  See post bloom and first cover control recommendations.

See New York Fact sheet, including photos of adult, eggs,  larva. and pupa.
See Michigan Fact sheet.