Vitis labrusca

While Vitis labrusca is considered a distinct taxon (Flora of North America 2016), certain accessions sampled from Virginia and Connecticut populations may not belong to the V. labrusca clade, based on molecular data. Further work is needed to determine if these populations represent species other than V. labrusca (Wen et al. 2018). Vitis labrusca hybridizes with V. riparia, resulting in Vitis x novae-angliae (Walker et al. 2019).

Vitis labrusca is a high-climbing vine that occurs throughout much of eastern North America. It occurs in a variety of habitats, primarily in areas that are moist to wet. Although its habitat has been impacted by threats, V. labrusca remains a widespread species. Vitis labrusca hybridizes with the cultivated wine grape (V. vinifera); cultivated hybrids such as 'Concord' continue to be used in the production of table grapes, jelly, and sweet wine. Some hybrids of V. labrusca have escaped cultivation and become naturalized in areas of North America outside of its native range.

Vitis labrusca is native to the eastern part of North America, occurring as far north as Ontario, Canada, and south to Georgia in the United States (Flora of North America 2016). The species is cultivated and has escaped cultivation in several regions of the continent, including the Pacific Northwest, the northeastern part of Canada (New Brunswick, Nova Scotia), southern California, and parts of the Midwest (e.g., Missouri). Flora of North America (2016) lists the following province and states as the native range of V. labrusca (ON, AL, CT, DE, DC, GA, IL, IN, KY, ME, MD, MA, MI, MS, NH, NJ, NY, NC, OH, PA, RI, SC, TN, VT, VA, WI). Herbarium specimens outside of the native range included in Flora of North America (2016) were not included in calculating the Extent of Occurrence. Specimens in Illinois may also be introduced; however, the rating assigned for the Extent of Occurrence would not change with the removal of locality data from Illinois.

Vitis labrusca is known from over 500 herbarium specimens and has a wide geographic distribution in the eastern part of North America. Therefore, there are inferred to be greater than 300 element occurrences.

Specific threats to V. labrusca are not well-documented. The habitat in which it occurs has been affected by development, agriculture, invasive species, and other threats common to eastern North America. However, since V. labrusca can occupy disturbed habitats, it is not possible to calculate the scope or severity of threats to this species.