Welcome to trhe squash vine borer society.-this nastly little worm is the scoiurge of summer squash. Injecting BT into the stems is a control--keeping the outside of the stem sprayed or dusted with a pesticide is another--digging the beast out of the stem when it first appears is another. Get your suash going as soon as possible in the spring and you may reach the zuke overload point by the time the nasty shows up and no longer want to see any more zukes