Synonyms

  • Vitis rubra Michaux
  • Vitis monosperma Michaux
  • Cat Grape
  • Bird Grape
  • Vigne de Chat

General Information and Distribution Range

Vitis rubra was described by Michaux based on specimens from the herbarium of the Paris Museum. In the course of botanical systematization, inaccuracies arose: Michaux partially confused this species with Vitis riparia, as confirmed by the study of his herbarium collections. The presence of Vitis riparia forms with small, deeply incised leaves that turn purple-red in autumn (described by Vahl as Vitis palmata) led to confusion. Dr. G. Engelmann also described Vitis rubra under the name Vitis palmata, which J. E. Planchon subsequently determined to be a synonym of Vitis riparia. Vitis rubra is closest to Vitis riparia but is sharply distinguished from it by its vegetative periods, seed characteristics, shoots, and leaves.

The species has a very limited geographical range and is considered almost extinct from the wild flora of American forests. In 1882, the researcher Eggert discovered small populations of the species on the banks of the Mississippi River (twenty miles north of St. Louis, opposite the town of Alton), and further north, along the banks of the Meramec River. Eggert's mentions of the species occurring in the Indian Territory are questioned, as the researchers H. Jaeger and P. Viala did not encounter this species during their explorations of that region.

The vine grows exclusively in rich ecological niches — on fresh or moist alluvial soils along riverbanks. On the Meramec River, the species is confined to deep, highly fertile black soils. Despite the richness of the soils, the trunk of wild plants remains slender, and cuttings root extremely poorly. For this reason, Vitis rubra held no practical interest as a rootstock. The researcher Millardet pointed out its value for artificial hybridization due to its resistance to Phylloxera and fungal diseases; he also recorded a natural hybrid, Cordifolia-Rubra.

Morphological Description

  • Habit of the vine and vegetative organs: The vines possess weak vigor and a climbing habit, scrambling over riparian shrubs. The trunk of wild specimens is slender, reaching no more than 5 centimeters in diameter. The bark is dark brownish-black and detaches in long, intersecting strips.
  • Shoots and tendrils: Matured annual shoots (sarments) are short, slender, angular, with a flattened cross-section in the node zone. Laterals are weakly developed and few in number. In the herbaceous state, the shoots have an intense purple glossy coloration and weakly expressed ribbing near the apex. Matured shoots acquire a matte reddish-brown color with weakly adherent bark, and the surface is marked with numerous fine longitudinal furrows. The inner wood has a greenish-white tint. The pith occupies about half of the total shoot diameter and is intensely colored. The diaphragms at the nodes are flat or plano-concave, very thick (up to 3 millimeters). The internodes are short and cylindrical. The nodes are clearly defined, covered with a glaucous bloom, and have a darker color compared to the internodes. Tendrils are intermittent, robust, bifid (two-forked), and glossy purple in the herbaceous state.
  • Leaf blade: The leaves are small, triangular-elongated, and the length of the blade always exceeds its width (average size is 9 by 8 centimeters or 7 by 5 centimeters). The leaf blade is distinctly asymmetrical, three-lobed, or in rare cases, five-lobed. The terminal lobe is strongly elongated into a long, slightly curved point (2 to 3 centimeters long). The upper lateral lobes also terminate in a prominent, well-developed tooth. The petiolar sinus is very widely open, and the lower margins of the blade sometimes form a straight line at the base; the "apron" is weakly developed and rudimentary. The teeth along the leaf margin are broad with deep incisions between them. The teeth themselves are rounded (blunt), but terminate in a long, thin point (mucro) directed toward the terminal lobe. The blade is thin, slightly parchment-like, and flat. The upper surface of the leaf is smooth, glabrous, and dark green. The lower surface is lighter, slightly shiny, and glabrous on the parenchyma; small tufts of short, stiff hairs are present at the branching points of the main veins. The veins are strong and project prominently on both sides of the blade. The petiole is long, slender, colored a matte dark purple, and covered with numerous short hairs in the form of a small brush.
  • Clusters and berries: The cluster is elongated, relatively large for a wild species, cylindrical in shape, and entire. The peduncle is long and slender. The berries are arranged tightly in the cluster. The shape of the berries is rounded (subspherical), and the size is small. The color of the skin when fully mature is intense black and shiny. The skin is thick. The flesh is low in juice, and the juice has a sweet taste with a light, refreshing acidity.
  • Seeds: Predominantly 2 seeds are formed in a berry. The seeds are large, almost spherical in shape (length is 6–7 millimeters, width is 3–6 millimeters). The color of the seeds is reddish-brown, and the surface is shiny with slight roughness. The depressions (fossettes) are wide, deep, with wavy margins, and their inner surface has a glossy yellowish tint. The beak of the seed is short and rudimentary. The chalaza is oval, bounded by irregular, prominent ridges, from which distinct radial furrows diverge. The chalazal depression is very deep, smoothly transitioning into a deep longitudinal groove that runs around the base of the seed and extends to the beak. The raphe is completely absent.
  • Vegetative features: Budburst, flowering, and berry ripening in Vitis rubra occur very late in the season.