Every year my compost pile produces some volunteer vegetable from the seeds that come from kitchen veggie waste. This year an especially large, healthy squash is growing out of the pile, but I can't figure out what type of squash it is. The squash seeds that have gone into the compost pile are Zucchini, Yellow, Acorn and Butternut.
The fruit on the plant has the characteristics of a Butternut, but the skin is green and the fruit is HUGE! I think if I continue to let it grow through October, I'll be able to use this squash for Jack'o'Lanterns.
I've included pictures of the plant and the fruit. Any help identifying this squash will be greatly appreciated.