The Carlisle Mosquito Online

Friday, June 3, 2005


Aliens among us

Garlic Mustard. (Photo by Kay Fairweather)

There is a new kind of Silent Spring at work in our environment. The agents of it are more insidious than DDT. They are not toxic chemicals. They are attractive and seductive but just like DDT, they have widespread and long-term repercussions that outweigh by far their initial allure. They are the aggressive non-native plants that diminish our biodiversity by out-competing the natives for moisture, light, nutrients, and space. They not only change the flora and create areas of monoculture (e.g. the massive stands of purple loosestrife at Great Brook Farm State Park) but they interfere with native plant-animal associations like pollination and they disrupt the food chain for the fauna.

Many alien plants are well-behaved but many are not. We need to be aware of the differences and become equally aggressive in our control of the invasives, else we remain unwitting participants in a relentless reduction in biodiversity.

What you can do:

•Learn which plants cause the problems.
•Eradicate them on your own property. This reduces the opportunity for birds and animals to disperse seeds.
•Talk to nurseries about the issue and ask for recommendations for alternate, native plantings.
•Talk to landscapers about plant selection. For example, many burning bush plants (Euonymous) are planted by landscapers because they (the bushes) are cheap, hardy, attractive and they grow quickly.

Finding the Aliens

This is not the "X-Files." We don't need Fox Mulder. We have Peter Alden. Peter is a noted naturalist and author who has a special interest in creating awareness and teaching control of invasive alien plants. He will be in Carlisle on Friday afternoon, June 10, to lead a walk starting at 3:30 p.m., and teach all comers to recognize some of these alien species. The walk will begin in the school parking lot on Church Street. Aggressive alien species will be tagged so that anyone who is not able to join the walk can visit later, spot the plants, and see the identifying characteristics.

Like all plants, some of these invasives are easiest to recognize when they are either flowering or fruiting. For example, right now while it is flowering is a very good time to find the Garlic Mustard plant, and interrupt its life cycle before it sets seeds.

Aggressive alien species

Some of the plants listed here may surprise you. Some are still being sold by nurseries. This is a very short list. Comprehensive lists are available from the web sites noted in the resources section.

•Norway maple
•Burning Bush
•Oriental bittersweet
•Non-native Honeysuckles
•Purple Loosestrife
•Garlic Mustard
•Black Swallow-wort
Web resources for more information — This web site focuses on work conducted by students and staff of the Ecology and Management of Invasive Plants Program, directed by Bernd Blossey, at Cornell University. The majority of their work concerns species and ecosystems in northeastern North America. — This is the web site of the Plant Conservation Alliance's Alien Plant Working Group, that provides information for the general public, land managers, researchers, and others on the serious threat and impacts of invasive alien (exotic, non-native) plants to the native flora, fauna and natural ecosystems of the United States. — This is the Invasive Plant Atlas of New England, managed by the Department of Ecology & Evolutionary Biology at the University of Connecticut.

2005 The Carlisle Mosquito