The ideal spray window for White Pine Weevil in NH is mid-April.

The ideal spray window for White Pine Weevil in NH is mid-April.

• A. Early February
• B. July
• C. October
• D. Mid-April

Answer: (D)

White pine weevil control relies on catching the adults when they are active and feeding on the new growth. The best time to apply a spray is when the leaders are just starting to flush and adults are actively feeding, so the insecticide can contact them before they lay eggs or bore into shoots. In New Hampshire, that window typically falls in mid-April, aligning with the beginning of new growth. Spraying earlier, like in February, means there aren’t active adults to kill yet and the spray won’t be effective. Spraying later, such as in July, often misses the critical period and won’t prevent the damage already done to the new growth. October is outside the active period altogether. So mid-April is the optimal timing to maximize control.

White pine weevil control relies on catching the adults when they are active and feeding on the new growth. The best time to apply a spray is when the leaders are just starting to flush and adults are actively feeding, so the insecticide can contact them before they lay eggs or bore into shoots. In New Hampshire, that window typically falls in mid-April, aligning with the beginning of new growth. Spraying earlier, like in February, means there aren’t active adults to kill yet and the spray won’t be effective. Spraying later, such as in July, often misses the critical period and won’t prevent the damage already done to the new growth. October is outside the active period altogether. So mid-April is the optimal timing to maximize control.