Invasive Species - Purple Loosestrife

Invasive 1 of 5
Next - Kudzu >>

Purple Loosestrife

What is it?

Also known as the “purple plague,” purple loosestrife (Lythrum salicaria) is an ornamental plant known for its purple-spiked flowers. Once limited to gardens in the Northeast, it now chokes wetlands across the country.

Why is it a threat?

Purple loosestrife has the ability to produce millions of seeds which spread easily by wind or water. Stands grow to thousands of acres in size, eliminating crucial open-water habitat for species such as butterflies and rare amphibians. Efforts to control purple loosestrife cost the U.S. economy an estimated $45 million each year.

How did it get here?

Purple loosestrife was brought to New England as an ornamental plant in the early 1800s. It has been promoted by horticulturists for its beauty and by beekeepers as a nectar plant.

How does it spread?

Each plant can produce millions of tiny seeds that can be spread by wind or water. Purple loosestrife lacks a natural predator, such as a beetle that feeds on its roots and leaves, in the U.S.

How can you remove it?

For small populations, hand removal and herbicides can work. Once a large population is established, however, it is extremely difficult to remove.

What can you plant instead?

Blazing star has spiked, pink-purple flowers and is an important source of nectar for many native species of butterflies and other insects. Consult your local nursery for other alternatives.