I think I have squash bugs, although they weren't on my squash. Now that I know what they are, I'm going to have to check my squash in the morning. Actually, I was trying to take some photos of my blooming yucca for an upcoming post when I noticed these bugs all over the flower stalk. It even looked like they might be mating - they were backed up against each other. Sorry for the slightly blurry photo - I wanted to get the closest photo I could. They seemed familiar, but I really didn't know where to start to figure out what they were. I had to narrow it down a little since there are a large number of bugs and insects out there. After consulting the "Basic Entomology" chapter of my MG training manual, I narrowed it down to bugs or beetles. Then I searched Google images for "beetle", "beetle pests" , and then "garden pests". Found on the first page of results was something that looked pretty similar to what I had - it was a squash bug.
I'm quoting from the manual: "Squash bugs overwinter in protected places as unmated adults. They appear rather slowly in the spring. They mate and begin laying egg clusters about the same time the vines begin to grow and spread. Eggs are yellowish brown to brick red in color and are laid in clusters of a dozen or more on the leaves. They hatch in about 10 days into nymphs that become adults in four to six weeks. Only one generation of bugs develops each year. New adults do not mate until the following spring."
So how does one control them? Advice on the subject varies, from not planting squash, to killing them as you see them. I may leave the ones on the yucca alone, but I'll make sure to check my squash and related plants for eggs on the leaves. If you have any, good luck with getting rid of them.