GALERUCELLA IS LOOSE IN SACO !!
The leaf-feeding beetle Galerucella.
If this sounds to you like an alien has invaded Saco, you're right! But – Galerucella has been intentionally introduced in an effort to control an insidious alien that has, in fact, invaded Saco and every other state in the U.S. except Florida. That uninvited insidious alien is PURPLE LOOSESTRIFE!
What is purple loosestrife? It is an erect perennial herb native to much of Europe, Asia and Great Britain that was introduced to the northeast U.S. and Canada in the 1800's for ornamental and medicinal uses. Most everyone would readily recognize the plant as the pretty, tall, purple flowers that grow prolifically along our roadside ditches and in our wetland areas. It is in bloom from June to September. True — it is a very pretty flowering plant. It is very picturesque when large areas of it are in bloom.
So, what's the problem? The problem is that purple loosestrife is an ecological threat. It adapts readily to natural and disturbed wetlands. As it establishes and expands, it out-competes and replaces native grasses, flowering plants and other vegetation that provide a higher quality source of nutrition for our native wildlife. Purple loosestrife forms dense, homogeneous stands that restrict native wetland plant species. As a result, our native wildlife suffers and, in many instances, is no longer able to survive in its former habitat. Unfortunately, the prolific expansion of purple loosestrife is unable to be controlled by our native insects or wildlife. It doesn't seem to taste good to our homegrown bugs, birds or wildlife.
Until recently, the control and management of the purple loosestrife infestation has been by labor-intensive hand pulling or by the application of herbicide chemicals. Both of these methods are costly and must be repeated every year to curtail the spreading of purple loosestrife.
More information about Purple Loosestrife may be found at the National Parks Service website.
While herbicides and hand removal may be useful for controlling individual plants or small populations, biological control is seen as the most likely candidate for effective long term control of large infestations of purple loosestrife. Enter Galerucella! In 1997 the U.S. Department of Agriculture approved three insect species from Europe for use as biological control agents. The leaf-feeding Galerucella beetle is one of them. This friendly beetle eats only purple loosestrife.
The City of Saco, largely through the efforts of the Conservation Commission, and most specifically Horace Wood, joined forces with the Rachel Carson National Wildlife Refuge, a division of the U.S. Fish and Wildlife Service, in a cooperative effort to raise and release the Galerucella beetle in Saco in an experimental program to control purple loosestrife.
In May, potted purple loosestrife plants were brought to wetlands in the former Saco Landfill. The plants were allowed to grow under controlled conditions. They were covered with fine netting sleeves and, when ready, ten to fifteen mature Galerucella beetles were introduced to each plant to reproduce. The netting, of course, prevented the beetles from escaping. They lay eggs on the leaves of the plant. The eggs hatch in 2-3 weeks and the larva feed on the foliage. The larva complete their development after 2-3 weeks of feeding and then they crawl to the ground and pupate within the top 1" of soil. Each potted plant is expected to produce 500 to 1,000 new beetles. Adults begin to emerge in another 2-3 weeks and also begin feeding on the loosestrife. They will feed for a few weeks and begin disappearing around mid August to over winter in the litter and soil around the host plant. They consume a vast amount of loosestrife when they are populous. Thus, the beetle cycle controls the proliferation of loosestrife.
Potted plants with their beetle populations have been placed in several locations in Saco where purple loosestrife is evident. The beetles will disperse to the plants in the area and begin a new cycle. We would welcome input from Saco residents and other interested parties regarding the location of purple loosestrife infestations. Several locations have been identified, but we are certain there are others we are not aware of.
Although the program is experimental in Saco, it has been deployed successfully in many areas around the country. We are very confident that our friends, the Galerucella beetles will find happy homes in Saco and work for us to effectively control the spread of purple loosestrife.
