Purple Loosestrife

Lythrum salicaria

Common Name: Purple loosestrife (purple lythrum, bouquet violet)
Scientific Name: Lythrum salicaria
Family: Lythracea
Growth Form: Herb
Native Range: Great Britain, central and southern Europe, Russia, Japan, China and northern India
Invasive Range: Southern Canada, northern and northeastern United States, scattered areas along the West Coast
Introduction: Purple loosestrife was introduced for ornamental and medicinal purposes.  Though it is recognized as invasive, it continues to be sold in nurseries.  Purple loosestrife produces by seed, as well as by shoots that are produced by its roots.  Stem fragments have the ability to root and form new plants.
Description: ·Leaves: Sessile or lanceolate, between 3 and 10 cm (1-4 in.) long.  Sometimes hairless, sometimes with short hairs that point upwards. Opposite, or in whorls of 3.  Base is heart shaped.

·Stem: Erect. 4 or 6 sided.  Sometimes hairless, sometimes with short hairs that point upwards. Plant can grow up to 2 m (6 ft.) tall.  30 to 50 from each rootstock.

·Flowers: Magenta; appear in long (10-40 cm, 4-15 in.) spikes from July to September.  5-7 petals.  10-14 stamensSepals are fused and enclose ovary.

·Fruit: Seeds small (1mm).  Reddish brown.  Many contained in each ovary.
Threats: Purple loosestrife forms dense stands in wetlands, where it can out-compete the native vegetation.  It restricts biodiversity, and displaces plants with nutritive value for local wildlife and destroys waterfowl habitats.
Fun Facts: In the past, the government used purple loosestrife to control roadside erosion.
Plant in seed

(c) Dan L. Perlman

Purple loosestrife in a wetland

(c)Dan L. Perlman