Biological control — Parasitic wasps can parasitize the eggs of L. botrana. Trichogamma species are known egg-parasites of many Lepidoptera species, and can be a good source of biological control of European grapevine moth. In the fall of 2009, egg parasitism was observed in Oakville in vineyards with L. botrana damage.

Studies are needed to determine how early in the season Trichogamma species begin to parasitize L. botrana eggs, if other species of native parasites attack the larval or pupal stages, and the impact these parasitesmay have onmoth populations. In France, Italy, and Spain, the highest parasitism is reported on the diapausing pupa stage. In Europe, green lacewings are among the main predators in summer and spiders are important predators of larvae and diapausing pupae.

Mating disruption — Female moths emit a plume of sex pheromone that males followupwind to find females and mate. Scores of dispensers loaded with synthetic pheromone and deployed throughout a vineyard cause the air to become saturated with the pheromone, such thatmalemoths are unable to locate females, preventing or delaying mating. In the absence of mating or if the female is too old when mated, viable eggs are not laid and no larvae are produced to damage grape clusters.

Mating disruption has proven most effective when European grapevine moth populations are lowandwhen synthetic pheromone is applied to large areas of over 10 acres or area-wide. If moth populations are high, supplemental insecticide applications may be needed.

At press time, no pheromone dispenser product has been registered for use in the U.S., though at least one manufacturer is seeking registration with the U.S. Environmental Protection Agency. The pheromone product undergoing registration is a handapplied dispenser that is attached to trellis wires or canes.

Mating disruption dispensers must be placed in the vineyard at the beginning of the male moth flight, as indicated by the first catch in pheromone traps. Follow manufacturer recommendations for the application rate of dispensers per acre.

Once mating disruption dispensers are registered for use and deployed in vineyards, the pheromone emitted by the dispensers coupled with the lure pheromone in the traps will cause very few moths to be caught in the traps (trap shutdown). Regardless, traps are useful to monitor a vineyard under mating disruption.

Place pheromone traps along the edges and in the center of the block. The edge traps give an indication of movement of male moths into the vineyard. The center traps should catch very few or nomoths. If the center traps are catching males, then mating is not being disrupted and supplemental insecticide applications may be needed. Monitor eggs at peak trap catch and periodically sample grape clusters for the presence of worms or damage.

Larvae can hide in tight places, and fully formed larvae may form a cocoon and pupate in any protected place. When hiring an outside company to harvest fruit, verify that the contractor follows good sanitation practices. Loads will need to be covered during shipment to the winery, and winery waste that does not undergo fermentation will need to be composted.