The only thing I've ever found effective against them is Sevin dust. Don't toss the squash out, though! Just soak them in water with a little vinegar, and the worms will come right out and you can use the squash.

Cody, to avoid the pickleworms in the future you have to be vigilant of the plants, inspect them every day if you can. I have one rule in my garden, I don't spray the leaves that I am going to eat like lettuce or greens. If you check the plants before they get the worms you can see a cluster of eggs and you can take care of those before they grow, you can apply Bt, Spinosad or Neem and they are organic. Next time when you grow them you can use light insect barrier covers or you can bag the fruit if it is big with pantyhose, time consuming but it works. Of course that is before they get the worms.:)

In my garden I am getting cucumbers and squash and they are fine, it probably helps that I was vigilant before when they were young.

Don't get discouraged, there is always a new season and a new chance to improve our garden skills.

Silvia

Bt is an acceptable treatment for caterpillars, if you're gardening organically.