That orange frass is the tell tale sign that one of those little jerks has burrowed into the plant. What they do is burrow into the stem and live there, eating the plant from the inside out. After about a month, when your plant is toast, they climb into the ground and go into a cocoon stage where they'll wait until next spring to hatch out as a moth. If you see this bastard around your garden, it's time to arm yourself.
And they leave little red eggs on your plants that look like this:
If you're not looking out for them, you probably won't notice anything is wrong until it's too late. You'll just kind of find your plants wilted and sickly, completely unaware that this son of a bitch is inside your squash or cucumber or watermelon plant, having a goddamn feast!
Once the borer has made it inside, there's really only two options to evict his ass. One is to carefully cut the stem of the plant open with a razor blade, extract the bug(s), and carefully cover the incision with soil in hopes that it will heal. F that noise. I'll take what's behind door number two. This option involves injecting BT into the plant. Here's what to do. First, you'll need a hypodermic needle.
I have a nurse mom so I've got the hookup, but I'm pretty sure you can get them at any pharmacy. Step two is to mix up a batch of BT, I use Thuricide, and fill up the needle.
"Don't worry squash plant, it'll just feel like a little pinch."
Now it's time for the fun part. Take the needle and inject it into the stem of the plant. You'll probably have to move the needle in and out some while trying to inject the chemical until you find the sweet spot. Do this in a few places along the stem so that you know there's nowhere for the little turd to eat plant guts without a BT marinade. I put about a syringe full in each plant.
Repeat these steps and inject all your squash plants. You're supposed to sterilize the needle with a bleach water mixture between each plant to prevent the spread of disease, but I was just too damn lazy to do it. If my plants all die as a result of trying to save them, well so be it.