Watercress (Fig. 18) is native to Europe and Northern Asia (Schardt and Schmitz 1990) and has a long history as a medicinal plant. It was used until the nineteenth century to prevent scurvy. Rollins (1978) stated that watercress was introduced into Florida at least by the early 1800's and probably much earlier. The watercresses have been prized herbs for salads or as green vegetables in Europe for centuries. They provide rich sources of iron, iodine, and vitamins A, B, and C (Anonymous 1976). Their introduction into North America and subsequent spread to Florida may be related to the use of watercresses as a food crop, although they are also cultivated to some extent for display in aquaria and aquatic gardens (Schardt and Schmitz 1990).
Watercress was reported at 12 sites during 1990, covered 5 ha of Florida public waters, and ranked 107th in abundance of recorded aquatic plant species (Schardt and Schmitz 1990). Watercress is a plant of temperate latitudes and consequently in Florida grows best in cool spring runs or in sluggish brooks (Godfrey and Wooten 1981). Managers regard watercress as innocuous.
Watercress (Nasturtium officinale) R. BR.
