Purple Loosestrife


Purple Loosestrife (Lythrum salicaria) Loosestrife family

Not yet found in Fairbanks area - Report immeddiately if found! Call 479-1213

A perennial plant which grows 2 to 8 feet tall. Produces tall spikes of purple-magenta flowers, each with 5 to 7 “ruffled”petals and a small yellow center. Lance-shaped leaves have smooth edges, and are usually arranged opposite one another, in groups of 2 or 3 along the stem. As many as 40 stems arise from the base of a well-established mature plant. Stems are 4 or 5-sided in cross-section.

An aggressive wetland invader, purple loosestrife chokes waterways, degrading wildlife habitat and fish spawning areas. Single plants can produce millions of tiny seeds.

Purple-pink flower spikes may be confused with Alaska’s native fireweed (Epilobiumspp.) but in Alaska purple loosestrife blooms in the fall, well after fireweed blooms have faded.

Not known to occur in Fairbanks; however, one infestation was found and is currently being managed in Anchorage. Look for purple loosestrife in wetlands.

More information


UAF Cooperative Extension Service    Alaska Association of Conservation Districts Alaska Department of Fish and Game Department of Transportation and Public Facilities – Northern Region U.S. Army Corp of Engineers Tanana Valley Farmers Market