Submersed or emergent perennial; stems weak to erect, arising from slender rootstocks or dense rosettes of leaves, usually simple but flowering stems occasionally branched, 4-8 dm long; submersed leaves dissected into numerous capillary divisions; upper cauline leaves oblong to lanceolate, entire or dentate, cuneate at base, lower emergent or partially submersed cauline leaves often transitional in form, entire, serrate, pinnatifid, or dissected; inflorescences elongated on widely spreading branches; sepals yellowish-white, erect; petals white; fruiting pedicels widely spreading, slightly ascending to slightly deflexed, usually straight, 1-1.5 cm long; siliques ellipsoid, 4-6 mm long, divergent on the same angle as the pedicels, shortly stipitate; septa perforate, residual as narrow strips on the inner margins of the replums; ovules numerous; styles 2-3 mm long with broad persistent slightly bilobed stigmas.
Flowers April - August. Quebec to Wisconsin, south to Florida and Texas. Rivers, streams, springs, ditches, sloughs, swamps and lakes. 2n = 24.
This species is not known to reproduce sexually, and despite occasional seed production, seed fertility has not yet been demonstrated. Sterility is attributed to triploidy which has been documented in Wisconsin, Michigan, Ohio and Vermont populations. Reproduction is exclusivley by vegetative means and nearly any fragment of a plant is capable of regenerating complete new individuals. Leaves detcach from plants at the slightest disturbance and account for much of the local spread of the species.
data regenerated on Fri, 12 May 2017 12:43:15 -0400