Purple Loosestrife

Effects on the ecosystem1. displaces grass and sedges2. homogeneous stands = no biodiversity3. restricts access to open water4. limits food and shelter for animals

Purple loosestrife was introduced to the US in the1800s. It was brought from Europe for ornamentaland herbal uses.It's preferred habitat is freshwater wetlands. It can tolerate many conditions but requires moisture to grow, and prefers full sun.

Purple Loosestrife is invasive

Definition: WatershedA region where all the water drains to a common body. Usually bounded by mountains.

Definition: Purple Loosestrife (Lythrum salicaria)~A perennial plant native to Europe and Asia~Grows 1.5 to 10 feet tall, with purple flowers~Has both a taproot and a spreading rootstock

Purple Loosestrife

This map shows the towns in Vermont with reported purple loosestrife in 1989, 1996, and 2005.Purple loosestrife is highly invasive and can destroy entire watersheds if left unchecked.

Purple loosestrife is invasive! - crowds or shades out native species - debris builds up around roots - kills floating vegetation by clogging waterways

This graph shows the estimated % of biomass that purple loosestrife made up from 1964 to 1978

- Hand-pulling can be effective on small stands- frequent cutting to ground weakens stand after several years

cuttings and fragments should be burned so they don't resprout

Control Efforts

Herbicides~glyphosate & triclopyr~effective chemical control~treatment best late in the seasonDownsides:~must be monitored for regrowth~Herbicides kill native vegetation

Biological solution1997, USDA approved 3 insect species from Europe~root-mining weevil~two leaf-feeding beetlesdo not seem to harm other plantsSome success with replacing loosestrife with other plants~Japanese millet~curlytop knotweed

Our best option?Ban the sale of purple loosestrife and continue with biological control methods

Still sold as a garden plant in some states!