Invasive Plant Getting Natural Control

Purple Loosestrife aren't blooming as they did in 2006!

2011 Update

Five years after the first release of the Galerucella beetle on the banks of the Naugatuck River, the invasive non native purple loosestrife has all but disappeared. Within that time frame, the beetle was munching away at the loosestrife while keeping all other plant material in tact. Now there is room for native species to return and flourish without competition. In past years, the banks of our rivers would now be exploding in color with the purple loosestrife flower, and a quick scan along the greenway shows not many are present.

Updated August 12, 2011

2007 Update

Beetles winning battle!

We are happy to report that Derby's effort to use Galerucella beetle to control the invasive growth of the Purple Loosestrife plant. seems to be working as you can see from this update from Ken Hughes:

"I took a walk down to the spot by the water where I released the Galerucella beetles last year. I noticed feed damage on the leaves of the Purple Loosestrife, and upon closer inspection, started seeing the beetles. I stopped counting at 150 beetles. This means the beetles successfully overwintered in the soil, and even survived the rising waters of the recent nor'easter. I even saw a few mating pairs. Each year their numbers will exponentially increase until the invasive plant is eradicated from the banks of the Naugatuck River."

Last year's effort was meant as a pilot project to test the feasibility of using the beetles, and the effort is showing great promise thanks to Ken Hughes' foresight - and word is already spreading about the success as Ken will be speaking to students at the Frenchtown elementary School who saw last year's article and want to learn more about this environmentally friendly method for controlling a major problem on the river banks.

As you walk along the new Derby Greenway, you will notice vegetation coming out of the rocks down by the water. This is the invasive Purple Loosestrife plant. This plant is highly noticeable towards the end of June, beginning of July when it is in full bloom, covering shores and wetlands with a tall, spiky purple flower. Although it looks pretty, it is a silent killer. It grows so quickly, it chokes out everything in its path. This invasive plant is quietly taking over Connecticut's wetlands - including areas along the new Greenway.

Purple Loosestrife is a serious concern because it grows and establishes quickly over wide areas and decreases the abundance of native species, reducing biological diversity in wetlands and other natural areas. Purple Loosestrife produces a high number of seeds and has an extensive underground root system. Birds do not eat the seeds, nor do they use the foliage for nesting. (Click here to read more about the plant.) Until now, Purple Loosestrife had no natural predators. Thanks to Ken Hughes, Chairman of the Derby Board of Aldermen, Derby is now taking steps to control the plant.

The Galerucella beetle may help control the Purple Loosestrife

Aldermanic President Ken Hughes puts his expertise to work for the benfit of the city.

Ken is a graduate of UConn's Plant Science program with a BA degree in Landscape Design, and is also a State Certified Pesticide Supervisor. The University of Connecticut has been studying a beetle, which exclusively feeds on Purple Loosestrife. The Galerucella beetle lives, feeds and breeds on Purple Loosestrife, and this plant alone. The beetle will overwinter at the base of the plants, and breed again the following year. Eventually, as their numbers increase, they will be able to naturally control the Purple Loosestrife plant. In conjunction with UConn, and with the permission of the Mayor, Ken has released some of these beetles along the shores of the Naugatuck river to help control the spread of Purple Loosestrife. This is strictly a biological control, meaning no herbicides will have to be used to in order to control this invasive plant.

To date, the Beetle program has released more than 838,000 Galerucella beetles into 76 wetlands in CT since 1996. This is the first time that they have been released in the Valley. Click here to read about a successful effort in King County, WA.

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