Got loosestrife? Now’s the time to check!

Today Katrina Scheiner, biologist at Great Meadows National Wildlife Refuge in Sudbury, Mass., shares the refuge’s efforts to control a highly invasive plant, purple loosestrife. In this photo, Katrina is pulling another invasive plant, water chestnut. Photo courtesy of Katrina.

What is purple loosestrife? You’ve probably seen it, and right now it’s in full bloom.

It’s a tall plant with spires of bright purple flowers that grows in wet areas. It’s very pretty, very invasive, and very hard to get rid of.

Purple loosestrife is a tall invasive plant with magenta-colored flowers that adapts to wetland areas. Once established, the plant begins to compete with native plants reducing natural habitats for waterfowl and other species which depend on aquatic environments. Credit: USFWS

Native to Europe, purple loosestrife was introduced to the U.S. in the early 1800s both on purpose, as a medicinal herb, and accidentally by way of contaminated ballast water on ships. It didn’t take long before loosestrife infested the eastern seaboard, and now it’s has spread through almost all of the U.S.

Purple loosestrife is remarkably difficult to remove for a number of reasons:

• Each mature adult plant is capable of producing tens of thousands of seeds;
• Its woody roots allow it to regenerate (so even after all your hard work, it might come back) and are difficult to pull up;
• It grows in wet areas, so mowing is not always an option; and
• Burning is not effective and may even damage native plants.

So how do we control this noxious weed? Many conservation organizations now use biological control.

Six different European insect species appear to be the most effective. They have been carefully studied to make sure that they don’t become an invasive problem themselves. They are host-specific, which means that they feed and reproduce solely on loosestrife.

An adult Galerucella beetle. Credit: Katrina Scheiner, USFWS

Two of the most successful insects are the Galerucella calmariensis and Galerucella pusilla beetles. The adults and their larvae feed on the stems and leaves, stripping the plant of its foliage and reducing its ability to flower and set seed.

Larva on the purple loosestrife. Credit: Katrina Scheiner, USFWS

After obtaining permission from the state environmental conservation department to release beetles, organizations can purchase beetles from a supplier. If there is an existing beetle population, they can bolster the wild populations by raising beetles in a rearing facility. Raising your own beetles can engage local conservation partners, volunteers and even youth groups.

Partnering with the Sudbury, Assabet, and Concord Rivers Cooperative Invasive Species Management Area, Great Meadows National Wildlife Refuge of the Eastern Massachusetts Complex ran a beetle rearing facility for the second year in a row this past spring.

“Beetle rearing facility” may sound high-tech, but we’re just creating a mock wetland environment. Plastic kiddie pools provide the water, and potted loosestrife plants provide tasty food for our beetles. We dig up loosestrife root balls in early spring and plant them in pots in the pools and let them grow until they’re tall and leafy enough to support beetles. If your facility is in a publicly accessible spot (we housed ours at Assabet River refuge’s visitor center), having signs or other outreach materials lets visitors know why you are actively growing an invasive species!

Removing mesh nets, which protect beetles, to release the beetles from the loosestrife. Credit: Katrina Scheiner, USWFS

After the plants are big enough, we slip fine mesh nets over them, supported by tomato cages or bamboo poles, and we collect wild beetles from local wetlands and add them to our netted pots. The nets keep the beetles in and predators out. Birds, amphibians and other insects all find Galerucella quite tasty, and we want as many of our beetle babies to survive to adulthood as possible.

Note the sign that we used to mark our plants. Credit: Katrina Scheiner, USWFS

After a little over a month of careful monitoring, the new generation of adults is ready for release! We grew 50 pots of loosestrife in our 2013 facility and estimate that we reared between 25,000 and 50,000 new adults. While that sounds huge, several thousand beetles are released for each infested acre.

Are you interested in starting your own beetle rearing facility? Right now is a great time to get started! Loosestrife is in full bloom, so now you can mark ideal sites to collect rootstock for your facility.

You collect the roots in early spring, when all that’s left are the dead sticks of the previous year’s growth. Flag each plant now, and collecting the roots in the spring will be a breeze!

Galerucella eggs. Credit: Katrina Scheiner, USWFS

Want to learn more? Visit our watershed blog or contact Amber Carr at amber_carr@fws.gov. Also be sure to check our Neponset River Watershed Association’s Flickr for hundreds of really great photos from their beetle raising efforts and all of their wonderful volunteers! You can also check out a similar effort led by our West Virginia Field Office.

Best of 2012 8) Controlling invasive species

We’re bringing in the new year with a look back at our milestones for 2012. Check back each day for featured events and activities from across the Northeast!

Invasive species pose some serious threats. They can displace native fish and wildlife and change native habitats, harming fish, wildlife and plant resources. Invasive species can also pose a risk to human health. In 2012, the Service worked to reduce the impacts that invasive species are having across the Northeast Region. A few projects that we worked on this year:

The first collection of hydrilla verticillata in Tonowanda Creek. Credit: USFWS

In September, staff at the Lower Great Lakes Fish and Wildlife Conservation Office discovered hydrilla verticillata, a highly invasive aquatic plant, in the New York State Canal System in Tonawanda, N.Y. Hydrilla crowds out waterweeds and other essential plants, slows water flow and can clog lakes and rivers, enough to even eliminate swimming or boating. The pest is confirmed within one mile of the Niagara River, and thus the Great Lakes. The extent of its possible impacts to the Great Lakes remains unknown, but monitoring elsewhere suggests the plant can become quite a nuisance in waters up to 25 or 30 feet deep. The Service’s Lower Great Lakes office is leading a rapid assessment team of state and federal agencies to determine the actual reach of the plant in the Tonawanda Creek and Niagara River corridor, which will help establish potential response options.

Galerucella beetles helped control invasive purple loosestrife in seven Northeast states in 2012. Credit: Katrina Scheiner

At the Eastern Massachusetts National Wildlife Refuge Complex, biologists reared between 17,000 and 33,000 Galerucella beetles to control purple loosestrife (Lythrum salicaria), an invasive wetland plant. The beetles feed on the leaves of purple loosestrife and reduce the growth and reproduction of the invasive plant. Purple loosestrife can lead to a decrease in plant diversity, resulting in a loss of wildlife diversity. Working with state partners and other organizations, Galerucella beetles were also released in six other Northeast states, including New Jersey, where the beetles were released in bog turtle wetlands.

Sea lamprey wound on an Atlantic salmon.

The sea lamprey (Petromyzon marinus) is a predatory fish that attaches to a host fish and feeds on it. Native to the Atlantic Ocean, a single sea lamprey can impact 40 or more pounds of fish in its life as a parasite. The Service’s Lake Champlain Fish and Wildlife Resources Office continued to evaluate and manage sea lamprey in Lake Champlain through state partnerships with the New York State Department of Environmental Conservation and the Vermont Fish and Wildlife Department. A number of techniques are used before determining an appropriate control strategy in a particular area. After permits are granted, control strategies are planned in detail among all three partners. The evidence of success is visible during pesticide treatments, but ultimately realized through decreased wounding rates and a healthier fishery.

Learn more about invasive species