Synonyms

  • Vitis bicolor Leconte
  • Vitis coerulea Munson
  • Goon Grape
  • Blue Grape
  • Winter Grape
  • Northern Aestivalis
  • Northern Summer Grape

General Information and Distribution Range

Vitis bicolor was described as a distinct species by Leconte. The viticulturist T. V. Munson initially isolated this vine from Vitis aestivalis under the name Vitis coerulea, but later identified it with Leconte's Vitis bicolor. Its morphological characteristics are not sharply differentiated from Vitis aestivalis, to which it was also referred by Watson. Nevertheless, Vitis bicolor maintains uniform and constant characteristics throughout the entire region it inhabits.

This species is native exclusively to the northeastern part of the United States, being most frequent in Michigan, Indiana, and New York State. To the south, its range extends to Virginia, and a few rare specimens have been observed in the province of Ontario, Canada.

Vitis bicolor grows only in soils of ancient geological formations (Carboniferous, Silurian, Devonian), which are red and fertile. The species is reported to be more resistant to Phylloxera than Vitis aestivalis, but it is less vigorous and holds no practical interest for commercial cultivation.

Morphological Description

  • Vine and vegetative organs: Vines are characterized by a climbing habit. In the fertile and fresh soils of forest areas, the trunk of the wild vine can reach up to 50 centimeters in circumference. The plant climbs over shrubs and high trees. The bark is thick, detaching early in intersecting longitudinal strips. The coloration beneath the detached bark has a dark brick-red hue. The wood is dense and fibrous.
  • Shoots and tendrils: Annual shoots are long, robust, with slight angularity. Broad, shallow furrows are present on the herbaceous shoots. The color of the growing shoot is wine-green with a characteristic glaucous waxy bloom. By the time of maturity, the shoots acquire a cinnamon-red color, becoming matte, with a faint bloom across the entire surface. Laterals are few. The internodes are long and cylindrical. The nodes are weakly prominent, making the tendrils appear pressed into their points of attachment. The bark of the matured shoot is relatively thick, adheres weakly to the wood, and detaches easily. The inner wood has a light yellowish-white tint. The pith is uniform, occupying about one-third of the shoot diameter, and is colored dark tan. The diaphragms are rudimentary or plano-concave, about 3 millimeters thick, sharing the same color as the pith, and are weakly lignified; the pith broadens in the diaphragm zone. Tendrils are intermittent, long, of medium thickness, and bifid (two-forked).
  • Leaf blade: The leaves of Vitis bicolor are characterized by less pronounced lobing compared to Vitis aestivalis. The leaf blade is entire or with weakly indicated lobes, rounded or ovate in shape. The upper surface of the leaf has an intense dark green matte coloration. The lower surface of the leaf blade is completely glabrous and features a distinct glaucous-blue tint. The absence of pubescence on the lower side of the leaf is one of the main distinguishing features of this species from the related Vitis aestivalis. The leaf texture is dense.
  • Clusters and berries: The cluster is small in size, significantly smaller than that of Vitis aestivalis. In structure, the clusters are dense and compact. The berries are small, spherical, and dark-colored. The skin of the berries contains a large amount of coloring matter. The flesh is low in juice, and relatively little juice is extracted.

Natural Hybrids and Their Characteristics

Under natural conditions, Vitis bicolor readily cross-pollinates with co-occurring wild grapevine species, forming hybrid populations:

  • Aestivalis-Bicolor: Numerous natural hybrid forms that are most frequently recorded in the states of Pennsylvania and Ohio. These plants represent a continuous transitional series from typical Vitis aestivalis to Vitis bicolor. Morphologically, they differ from pure Vitis bicolor by a more pronounced downy pubescence on the lower side of the leaves and a larger berry size. These hybrids hold no cultural or economic value.
  • Bicolor-Riparia: A rare natural hybrid discovered and described by the viticulturist T. V. Munson in the province of Ontario, Canada. This plant possesses a specific set of characteristics: the leaves are rounded, thick, with highly prominent, relief veins on the lower side. The veins are covered with soft, short hairs, characteristic of the tomentose forms of Vitis riparia. The lower surface of the leaf has a matte blue-green tint, while the upper surface is dark green and matte. The leaf blade is divided into five distinctly expressed lobes with long and sharp teeth along the margin. The petiolar sinus is widely open, the "apron" is virtually absent, and the marginal teeth are arranged in two clearly defined series.