Purple Loosetrife

Scientific Name: Lythrum salicaria
Family Name: Lythraceae

Flower: Long spikes of purple flowers that are .5 - .75 in. (1.5 – 2 cm.) long with 4 – 6 petals.

Leaf: Lanceolate leaves that turn heart-shaped at the base, 1.5 – 4 in. (4 – 10 cm.) long. Leaves are usually opposite, but also grow in whorls of three.

Plant: Loosestrife is very tall, growing 2 – 4 ft. (60 – 120 cm.).

Identifying Characteristics: The tall loosestrife plant with impressive purple flowers cannot be mistaken for anything else.

Location: We saw Purple Loosestrife in the wetland area behind the Goldfarb library at Brandeis University.

History and Comments: Purple Loosestrife was introduced to the Northeastern United States from Europe in the early 1800's, either from ship ballast, or from seeds attached to imported sheep. It was later planted for ornamental purposes, and by the 1900's, it had escaped cultivation, and now it grows as immense fields in wetland areas that choke out all native vegetation. According to the United States Department of Agriculture, it is classified as an invasive species by 35 states. For more information from the USDA, click http://plants.usda.gov/cgi_bin/plant_profile.cgi?symbol=LYSA2. Purple Loosestrife completely destroys all other wetland plant life, and is quickly spreading to wetlands and meadows throughout the United States.

    Unless otherwise specified, all text, photographs, and drawings are Copyright (c) by Shu-Yee Chen and Deborah Hamer 2003. No part of this page may be reproduced without prior written consent of the authors.