This is widely naturalized across temperate North America. Short (1837) provided the first clear record from Ky. It occurs mostly in sunny calcareous springs or associated streams, and now much more widespread in calcareous regions than records suggest. In Ky. plants are especially dense and robust (to 1 m tall) in some springs of the Bluegrass region, perhaps due to high phosphate levels in the soil. The plant provides a highly nutritious food for humans ("watercress") that was introduced by pioneers, especially at suitable springs that were important for early "improvements" on the frontier. Plants are especially rich in several vitamins and isothiocyanates that inhibit cancers, reduce inflammations, kill intestinal worms and repel ticks (e.g. Palaniswamy et al. 2003, Schulze et al. 2021); see also notes under Armoracia which is closely related. The species is generally avoided by livestock, but wild turkeys may consume it (Goerndt et al. 1985). JC still collects it for food (and resultant physiological benefits) much more than for the herbarium, avoiding watersheds with livestock due to danger of parasites or pathogens. Reportedly, the danger of liver-flukes from livestock can be eliminated by cooking or washing in 6% vinegar for 10 minutes (https:// patient.info/ doctor/ fasciola-hepatica). The perennial decumbent rooting stems of this plant should initially be called stolons (Rollins 1993), but they tend to become covered with sediment, then rhizomatous with age (Y). Although Nasturtium has often been combined into Rorippa, the genus is closer to Cardamine (Y, FNA 7). Curiously, there are native species of Nasturtium in Central America, southern Califormia and Florida; but officinale is considered alien in North America (FNA 7).