Purple Loosestrife

Description:

PURPLE LOOSESTRIFE - Lythrum salicaria L.

Lythraceae - (Loosestrife family)

A rhizomatous perennial with erect stems, often growing 6 to 8 feet tall, usually associated with moist or marshy sites. Leaves are simple, entire, and opposite or whorled. Rose-purple flowers having 5 to 7 petals are arranged in long vertical racemes.

Purple loosestrife, is an introduced European Ornamental species that often escapes to aquatic sites such as streambanks or shorelines of shallow ponds. Infestations can become dense and impede water flow in canals and ditches. Reports of reduced habitat for wildlife use are common.

Non-standard name: purple lythrum.

(Courtesy of Weeds of the West)

Control Strategies:

While this weed is wide spread and very damaging in the eastern part of the US, it is not common in Wyoming to date. It occasionally is found in flower beds where it was intentionally planted. Dig it up. The seeds are small and can be moved to other sites where the weed will quickly dominate. Once established in riparian sites the only herbicide of use is one of the aquatic formulations of glyphosate which of course kills everything. Prevention is the best approach at this time in Fremont County.

To learn about biological control agents for Purple Loosestrife visit this link.