Grape plume moth

The Grape plume moth (Oxyptilus periscelidactylus) is a member of the Pterophoridae family, order Lepidoptera. This insect is named for its distinctive wing structure, where the wings are deeply cleft into plume-like lobes. Although small, this moth can be a significant localized pest in viticulture, particularly in North American grape-growing regions.

The host range is largely confined to the genus Vitis. Both wild and cultivated grapevines are susceptible to damage. The pest is strictly monophagous in its feeding habits, targeting the most succulent and nutrient-rich tissues during the early growing season of the vine.

The life cycle begins with larvae emerging from overwintering sites as the grape buds start to swell. The young larvae migrate to the tips of the shoots, where they use silk to web together terminal leaves and flower clusters. This structure serves as a protected feeding chamber, allowing them to consume the developing buds and leaves undisturbed.

The primary damage caused by this pest is the destruction of flower clusters, which leads to a direct reduction in fruit set and overall yield. In cases of severe infestation, the vegetative growth of the vine is also stunted, which can weaken the plant's physiological capacity to store energy for the following season.

Integrated Pest Management (IPM) is essential for controlling this moth. Strategies should be timed with the phenology of the vine to ensure efficacy:

• Scouting for webbed terminal leaves in early spring.
• Manual removal of infested clusters in small-scale vineyards.
• Application of Bacillus thuringiensis sprays at the first sign of larval activity.
• Strategic chemical control using insecticides if the economic injury level is reached.