Recent studies in some states have shown mating disruption with synthetic pheromones to be an effective alternative in situations where there is no immigration of moths from outside sources. Mating disruption relies on releasing enough of the pheromone in the vineyard so that males cannot find female moths. Commercial systems available for mating disruption for this insect are recommended for vineyards at least 5 acres in size. Grape Phylloxera Grape phylloxera is native to eastern United States, but has been distributed to other grape regions of the U.S. and is also established in Europe where it is of great economic importance. The leaf galls caused by grape phylloxera are unsightly and do little damage, however, infestation of the roots can be difficult to control and can lead to decline of vines.
Severe infestations can cause defoliation and reduce shoot growth.
Hosts include cultivated and wild grapes. The winged forms, which are less apt to be seen, are also aphid-like, except that wings are held flat over the back. Neither winged nor wingless forms have cornicles, tail pipe-like structures on the top of the abdomen, as aphids do. The presence of grape phylloxera is best recognized by characteristic galls it produces on the leaves or roots. Root galls are knot-like swellings on the rootlets, and may lead to decay of infested parts.