Purple Loosestrife

Lythrum salicaria

Description

An upright, bushy perennial aquatic plant that blooms mid-summer and grows up to nine-feet tall. The magenta flowers have 5-7 petals and grow numerously on a long spike.

Habitat

Freshwater and brackish wetlands

Distribution

Throughout most of Oregon, Washington, and Idaho

Impacts

Crowds out marsh vegetation that is required by wildlife for food and shelter; heavily infested areas have demonstrated decreased waterfowl and songbird production

Dispersal Methods

Water, wind (minimal), transport through wetland mud by animals, humans, boats, or vehicles

Prevention

Look for purple loosestrife along river and lake shorelines, wetlands, ditches, and wet pastures. Best survey time is July and August when plants are in flower; look for seedlings in June. Clean off equipment, shoes, clothing and animals that have been in infested areas to prevent spread.

Listings

ODA's B List

Factsheets

Washington State Noxious Weed Control Board Fact Sheet

Photos

Idaho Weed Awareness Campaign Virtual Slideshow

Distribution Map

Distribution in Oregon
Distribution in Washington
Distribution in Idaho

CWMA Warnings

Mid-Coast

WEEDIN

Multnomah Weed Watchers