I know what you're thinking -- provided that you are aware that squash cross-pollinate -- How can you have volunteers of something that cross-pollinates? Well, the fun part is that you never know exactly what you're going to get. It's like Christmas. We had one volunteer that looked a lot like a spaghetti squash. It was a little sweeter than spaghetti squash, and it wasn't quite as stringy, but it was delicious, and we enjoyed every bite. This is the first year that I decided to eat the volunteer squash that grew next to a compost pile. It seems silly that we never did it before. This one looks like a cross between an acorn squash and something. Aren't they beautiful!
If you're new to gardening and wondering what I'm talking about -- well, you can't save squash seeds and expect to get the same squash again if you grew more than one variety. You'll get some odd cross between the two. Not everything in the garden will cross pollinate, but squash is one that will. So, if you want to save seeds from your squash, you can only grow one variety, or you can put them in isolation tents and hand pollinate, which I'm not going to do.
Thanks to Katherine for the photos!