Surprised to be finding small grapes this late in the year? You found frost grapes aka river grapes (Vitis vulpina). Like mustang grapes, they are too tart for an enjoyable raw snack, but make great jelly, jam, or wine. Leaf Arrangement: The leaves of Vitis vulpina are arranged alternately along the stem. Leaf Shape: Leaves are typically palmately lobed, with three to five lobes, each lobe being broadly ovate, measuring approximately 2 to 5 inches in width. Leaf Venation: Pinnate venation, with