I was looking at my plants yesterday and noticed that two of my squash plants looked quite sad. Upon closer inspection I discovered the problem. The stems near the root were mangled and damaged. I moved the plant and it just fell apart. Inside were a bunch of worms. I'm guessing that these are the dreaded squash vine borers.
I removed the two damaged plants and mulched them with the mower. Maybe I should have fed those bugs to the chickens instead.
Luckily, my other two squash plants appear to be ok. Time will tell I guess.