Vine vigorous to very vigorous, climbing. Shoots cylindrical or slightly angled, usually smooth, slender; diaphragms thin; tendrils intermittent, slender, usually bifid. Leaves with large stipules; leaf-blade medium to large, thin, entire, three, or lower ones often five-lobed; sinuses shallow, angular; petiolar sinus broad, usually rather shallow; margin with incised, sharply serrate teeth of variable size; of a light green color, glabrous above, usually glabrous but sometimes slightly pubescent on ribs and veins below. Cluster medium to small, generally compact, shouldered; peduncle short. Berries small to medium, black with a heavy blue bloom. Seeds usually two to four, small, usually slightly notched, short, plump, with very short beak; chalaza narrowly oval, depressed, indistinct; raphe usually a groove, sometimes slightly distinct. Very variable in flavor and time of ripening. (See Plate.)
The first mention we have of _Vitis riparia_ is by Tournefort in 1700, who, without further description, calls it _Vitis canadensis aceris folio_, or Maple-leaved Canadian grape.[135] Linnaeus in 1753 described mixed specimens of Cordifolia and Riparia under the name of _Vitis vulpina_. His description is as follows:[136] "Leaves cordate, dentate-serrate, glabrous on both sides." Walter and Willdenow copy the description of Linnaeus. The first description which is clear, and the identity of which has never been questioned, is that of Michaux in 1803, under the name Riparia. He says: "Leaves unequally and sharply dentate, slightly 3-lobed. Petioles, veins and margins pubescent. Called by French residents _Vigne des battures_. Habitat along the banks and on the islands of the Ohio and Mississippi rivers, etc." Bartram, in 1804, under the name of _Vitis serotina_, or Winter grape, describes a vine which may be Riparia or may be Cordifolia as it has some of the characters of both.
Linnaeus' description seems to have thoroughly confused all of the earlier botanists. They were in doubt, first, as to what species was intended for Vulpina; second, as to the distinguishing characters between Riparia and Cordifolia. Gray classed Riparia as a variety of Cordifolia. Engelmann was the first to draw attention to the specific characters which separated these two sorts and these he gives as follows: 1st. Riparia has thin diaphragms, Cordifolia thick. 2d. Riparia blooms early, Cordifolia late. 3d. Riparia propagates readily from cuttings, Cordifolia only with difficulty. 4th. Seeds of the Riparia have indistinct or almost indistinct, depressed chalaza and raphe, while the chalaza and raphe of the Cordifolia seeds are elevated and distinct. To these Bush[137] added the further distinguishing character that on the shoots the small terminal leaves of the Cordifolia open as soon as formed, while those of Riparia remain folded for some days after they are formed, become larger and then expand gradually.