By NORA BODRIAN
The desert wild grape (Vitis girdiana) is endemic to Southern California and Baja California. Other common names are coyote grape and valley grape.
It can be found in riparian habitats, such as along the San Diego River near Gate 9 in Mission Trails Regional Park. It is a woody vine, with a coating of wooly hair on heart-shaped leaves with serrated edges, similar to maple leaves. As a deciduous vine, it can grow 30 feet in length, with leaves turning all shades of yellow and orange in the fall. The vine uses its tendrils to anchor on to surfaces, often overtaking other plant species. The grapes grow in bunches from pale yellow flowers, and the grapes are much smaller and darker than European grapes.
Native Americans used the roots, leaves, and fruit as food, drink and tonic to relieve pain, treat diarrhea, fevers, liver troubles, and rheumatism. The sap of the grape stems was collected and rubbed on falling or thinning hair to keep it healthy and darkened.
The grapes can be eaten fresh but were traditionally gathered and dried like raisins and stored for use throughout the year. The small dark purple grapes are a food source for birds, the leaf foliage provides a thick cover for hiding, and the flowers are visited by bees and butterflies.
Native grape vines existed well before the Europeans came to the Americas: in fact, there are hundreds of native varieties. The vineyards in California cultivate the European grapes that were introduced by missionaries and European settlers, and California produces more wine than all other 49 states combined. However, native wine grapes have always been widely used in the eastern United States and Canada, where the weather is too cold for European grapes. East of the Rocky Mountains, three-fourths of the grapes are hybrids of native and European varieties.
When European winemakers were experimenting with American grape vines in the 1800s, an aphid-like bug, Phylloxera sp., accompanied the grape vines on the steamships to the Old World. These bugs caused the Great French Wine Blight in the 1850s, destroying 40% of the French vineyards. The whole European wine industry was devastated for two decades while winemakers desperately sought to identify the cause and stop the blight. Eventually the agricultural grafting strategy used on fruit trees was applied to grape vines. Since American vines had built up a tolerance to the aphids, French wine vines were grafted onto the resistant rootstock of American wild grape vines.
Grafting wine vines to native American rootstock is now a common practice in viticulture around the world. Our native grapes may not be as plump and sweet as the European grape, but their hardy roots are international champions.
—Nora Bodrian is a trail guide at Mission Trails Regional Park.