ajsmama- If your grapes have a foxy/musky smell and taste then they are probably Fox grapes, Vitis labrusca. To be sure you could check the tendrils. Fox grapes usually have tendrils opposite every leaf, whereas other wild grapes don't. Concord is in this species, although it's bigger and not as foxy as it's wild cousins. Riverbank grapes, also called Frost grapes, don't have a foxy smell or taste but they are quite tart. The name Frost grapes refers to the fact that they are supposed to be sweeter after a frost. And they grow pretty much everywhere, not just next to riverbanks. As for it's tendrils, they will usually be opposite one or two leaves in a row and then skip a leaf. To add to the confusion, there is a wild grape called Frost grape, Vitis vulpina. And there is also a variety of wild grape called Summer grape, Vitis aestivalis. But I highly doubt the OP has one of these. Of course, this info really only applies to the Midwest. Once you start going south and elsewhere you run into different species and wild muscadines and such. Rodney

Some good ideas, here -- I'll give them a try! I'm trying to figure out what made the difference in the harvest this year. In previous years there were a fair amount of grapes, but in previous years they were almost all green and painfully sour. Last fall my boss cut the vines waaaaay back, to the main trunk. This spring the vines quickly re-covered 20' of chain link fence, and set double the number of grape clusters. Which, for the first time, all ripened to a nice dark purple. I'm tempted to think the hard cut-back led to the growth spurt and the number of clusters, but the unusually gentle summer weather led to the wonderfully ripe fruit. At least one of those we can replicate next season!

You could try covering part of a runner with dirt and after a while, couple weeks or so cutt it loose from the original vine but leave it in the ground where it is and see what happens. If is fox grapes they do not very well in direct sun they do well in part sun/part shade

Wild grapes with larger fruits are likely forms of or hybrids involving Vitis vinifera. The most common native grapes in NY are Vitis aestivalis, V. vulpina, V. riparia, and V. labrusca. The latter two are quite difficult to tell apart. They normally have small, blue-black fruit, a "foxy" flavor, and usually become more palatable after frost. Cornell has a website devoted to grape culture but I don't know how useful it would be for identification Here is a link that might be useful: Cornell - Grapes