Q. What does a wild grape look like?
Native grape Vitis lambrusco is known commonly as the fox grape or plum grape and is frequently found climbing high into trees.
The leaves should be serrated, with hairy undersides and somewhat heart-shaped. There should be tendrils located along the stem opposite each leaf. The grapes have slip skins, that is to say the skins slide off easily (as they appear to have done in your photo). The flavor is described as "foxy" (thus the common name), musky or sweetly earthy and they are popular with birds and wild animals.
The concord grape, Vitis lambrusco 'Concord' is a cultivar of this species. Vitis lambrusco 'Niagara' is a white fruited descendant of 'Concord' that is the primary white table grape produced in the US today.
-NYBG Plant Information Service