Be on the lookout for squash beetles. They'll eat your entire squash plant burrowing into the vines and main stem.
Adult squash beetles lay eggs at night on the under sides of leaves. Make it a routine and check the under sides of all the leaves on your squash plants every morning. Use a plastic knife and scrape off the eggs.
Don't wait. Once you see the Nymphs crawling around the undersides of the leaves, it'll be too late.
Squash Beetle Nymphs
Squash Beetle Eggs
Nymphs and Eggs
