Limnobium spongia (Hydrocharitaceae) discovered in New England

摘要

L. spongia was discovered growing in a small pond (Knowlton Pond) 1.5 miles east of Storrs, Connecticut, in September 1998. Because this is considerably north of its normal range, it was concluded that that population would probably not persist. A survey of the site in May 1999 failed to detect any surviving plants. The following aspects of the species are discussed: the source of its introduction, dispersal in the USA, its inclusion in the diets of ducks, its occurrence as a weed in North Americaand the implications of an extension in its range.