Beware of the Squash Vine Borer, who lay their eggs at the base of vines of curcubit.
The biggest enemy to your squash will be the hideously hard-headed Squash Vine Borer. The adults emerge in June and lay groups of small, blood-red eggs at the base of the vines of curcubit: cucumbers, squash, pumpkins and melons. If you don't notice and crush the easily spotted eggs, they hatch and the larvae drill in and begin eating their way up the stem — always toward the growing end. Leaves wilt and blossoms dry up and drop as the larvae pass. You can squash them inside the hollow stems or use a wire to winkle them out. Bury the operated-on sections of stems and they should recover. Egg-laying adult females seem to prefer summer squash. Their larvae are unable to drill into the tough stems of even young butternut winter squash. Some experts suggest planting only butternut, using first sets of small fruit as a fresh vegetable and letting later fruit mature for storage.