This widely cultivated species (usually known in North America as "English ivy") is native to the oceanic climate of western Europe (Metcalfe 2005). Most plants in eastern North America are tetraploids, within the context of most Araliaceae (2n = 48). But octoploids are also cultivated and may be expected to escape (W, Y), usually known as a distinct species or ssp. hibernica (G. Kirchn.) D.C. McClint; common names are "Irish" or "Atlantic" ivy. The latter can be distinguished by its yellowish- to rusty-brown stellate hairs (versus whitish), with rays parallel to leaf surface (versus erect); also juvenile leaves tend to be larger, more uniformly medium green (versus marbled dark green and white), and less deeply lobed. Hedera has become locally abundant at scattered sites in southeastern states, as well as along the Pacific coast (where mostly hibernica), with much local vegetative spread. In some more interior regions, plants have not been able to tolerate winters as high vines, though they may persist as ground-cover. In Ky., there has been virtually no evidence of establishment from seed until recent years. Flowering occurs during the fall or mild winters, and subsequent production of seed may generally fail due to cold. However, several seedlings did appear below an old vine in JC's garden during 2012, and R. Weber (pers. comm.) has observed also observed seedlings in Lexington. The species is potentially used by honey-bees for a desirable honey, with unusual chemistry (Makowicz et al. 2018). See also general notes on ecology of evergreen vines under Euonymus fortunei. Both species may be reduced by browsing of deer and livestock in winter (Fargione et al. 1991, Campbell 2013). Hedera may also be sensitive to fire, with relatively volatile leaves that burn well (Waggy et al. 2010; pers. obs.).