• 
• 
• 
• 
• 
• 

		The Nature Conservancy in New York New York Home Contact Us Places We Protect   Adirondacks   Central & Western   Eastern   Long Island   New York City News Room Field Trips and Events Young Professionals Internship Program Science Volunteer Ways of Giving

The Galerucella beetle can reduce the growth and reproduction of purple loosestrife by feeding aggressively on its leaves and stems. Help Us Fight Invasives! With your donation, we can protect New York's environment from harmful invasive plants and animals.  Donating online is fast, easy, and safe. Invasive Species Resources Purple Loosestrife Factsheet Invasive Species Task Force Invasive Plant Council of New York State Native Plant Nurseries in New York State The Nature Conservancy's Global Invasive Species Initiative

Together with Cornell University and the Department of Environmental Conservation (DEC), the Central & Western Chapter of The Nature Conservancy is releasing a biological control for purple loosestrife. In the 1990s, researchers from Cornell traveled to Europe and identified all insect species commonly associated with purple loosestrife; six were chosen for further examination and testing.

Exhaustive research was conducted to find the most suitable species. Only insects that specifically target purple loosestrife were considered for introduction, and only after it was proven that they would cause no harm to native North American plants was the insect chosen for introduction.

In the end, the researchers found four distinct insects, including root weevils and foliage-foraging beetles, which feed on loosestrife and nothing else. Last summer, the Conservancy, together with Cornell and the DEC, released 50,000 Galerucella beetles into the dunes and wetlands of the Eastern Lake Ontario shoreline, an area renowned for its freshwater ecosystem.

Galerucella beetles dine exclusively on the leaves and stems of purple loosestrife. This spring, the Conservancy will release 1,800 root weevils at those same sites in an attempt to control the purple loosestrife from all angles.

Already the results are promising. In several test sites, Galerucella release has resulted in complete defoliation of loosestrife stands, eliminating nearly 95 percent of the infestation. Along the Lake Ontario shoreline, it is clear that the stands have been affected, and researchers have observed a resurgence of cattails and other native wetland plants. “After only a few months, it looks as if someone went out in the middle of the loosestrife stands and shot a BB gun through all the leaves. The results have been really amazing,” says Chris Lajewski, Northern New York Land Steward for The Nature Conservancy.

While only time will tell if this biocontrol effort will be successful in permanently reducing the presence of purple loosestrife, the outlook is promising. “We’re spreading the words, not the weeds, when it comes to biocontrol in northern New York” says Lajewski, adding that a return to balance may yet be possible.

 

<< Previous 1  2

<< Back to Nature New York Spring/Summer 2007

Nature picture credits (top to bottom, left to right): Photo © Mark Schwartzlaender (Galerucella beetle); Photo © The Nature Conservancy (Purple loosestrife)