Cultivars of Cucurbita pepo make up a large number of the squash and gourd varieties, particularly summer squashes. Cultivars include: pumpkin, pattypan squash, acorn squash, spaghetti squash, calabaza, yellow summer squash, zucchini, crookneck squash, ornamental gourds and many others. It is hard to tell which cultivar you find when it is seen growing as a weed if it has not begun to fruit. The example in the two pictures above, for instance, was pulled right after these pictures were taken. I was glad that it did not happen until it flowered. The example pictured directly below is taking over a Sedum planter.