Bogs and Acidic Peatlands of Southern New England by Marsha C. Salett
Decodon verticillatus (L.) Ell.
LYTHRACEAE (Loosestrife Family)
EtymologyDecodon means ten-toothed, in reference to the calyx which has ten teeth, from the Greek: deka = ten + odous = tooth; verticillatus means whorled, from the Latin: verticillus = whirl of a spindle + atus = is ike.
Synonyms (Common Name)Water Willow, Water Oleander
DescriptionSwamp loosestrife is a perennial shrub or semi-shrub with stems 3-10' tall that die back in winter. The semi-woody, arching stems have soft, spongy tips that root when extended into the water, acting as a framework on which sediments, vegetation, and peat accumulate. In this manner, swamp loosestrife helps form the leading edge of a floating peat mat.
Wetland indicator statusOBL
Plant Height2-6 feet
LeavesDeciduous, broad-leaved, opposite or in whorls of three or four; entire, to 6" long; lanceolate, with finely tapered point, sessile or short-stalked.
Flower/InflorescenceMagenta, 1/2 - 3/4" long, with urn-shaped calyx, 5 petals, 5 long stamens and 5 short stamens; short-stalked, in feathery clusters of 4-5 in axils of upper leaves.
Flowering PeriodJuly-August
FruitSmall, brown, roundish capsule with 3-5 locules or compartments.
Fruiting PeriodSeptember, persist until the stems die back in winter.
HabitatShrub swamps, open areas in bogs and poor fens; shallow edges of ponds, lakes and rivers; leading edge of floating peat mat.
RangeMaine to Illinois, south to Florida and Louisiana.
(c) 1998-2006 Marsha C. Salett