Vitis longii W.R. Prince & Prince
Vitis acerifolia is a species of grape native to the south-central part of the Great Plains of the United States (Kansas, Oklahoma, northern Texas, eastern Colorado, and northeastern New Mexico). Its leaf shape is the origin of its name, which is Latin for maple-leaf grape, but it is widely referenced in literature by the synonym, Vitis longii.
Vitis acerifolia is second in cold-hardiness among grapes only to Vitis riparia. Unlike other cold hardy grapes, it will grow long into fall if weather is clement, but can harden off remarkably fast in a cold snap. This makes it ideally suited for North American winter weather which often include sudden fluctuations in temperature, and is superior in this regard to its rival for second place in cold hardiness among grapes, Vitis amurensis, which is notorious for coming out of hibernation during a warm spell only to be damaged by a sudden frost.
Aside from cold hardiness, Vitis acerifolia provides many potential benefits for the breeding of hybrid grapes. It strongly resists drought, is resistant to phylloxera, is easy to root, has seeds that germinate all at once and it has good to excellent general resistance to other common grape diseases. While berries and clusters are generally small and seedy, it lacks the 'off flavors' of many other North American Vitis species, having neither the harsh labrusca aftertaste nor the characteristic herbaceous flavor of Vitis riparia, nor the blackcurrant-like flavor common to post oak grapes or the harsh peppery taste of many other native Texas grapes. Low acidity and very early ripening are also important characteristics for potential grape breeders.
It also yields strongly colored juice, lending its parentage to the Canadian variety 'Vincent' and similar varieties, which have concentrations of up to a dozen times more coloring than vinifera varieties used for the same purpose. Since red wines are fermented on the skins and this is the source of 'off' flavors in hybrid wines, it is notoriously difficult to produce cold hardy, quality red wine grape varieties. There are even fewer capable of adding strong coloration to weaker-colored juice varieties. Acerifolia hybrids show much promise in this area.
Although it has no inherent resistance to Pierce's disease, an important and deadly disease of grapes in the southern parts of the United States and Central America, it seldom suffers from this disease due to being almost totally unpalatable to the common insect vector of the disease, the glassy-winged sharpshooter (Homalodisca vitripennis). This is apparently due to the pubescence of the leaves repelling the insect.
- Biota of North America Program 2014 county distribution map
- Great Plains Flora Association. 1986. Fl. Great Plains i–vii, 1–1392. University Press of Kansas, Lawrence