What are Invasive Plants?

Invasive plants are non-native plants that are disruptive in a way that causes environmental or economic harm, or harm to human health.  In Connecticut, the Connecticut Invasive Plants Council has developed a list of non-native plants that cause (or have the potential to cause) environmental harm in minimally-managed areas.

Invasive plants are defined as having:

-  a high reproductive rate.

-  the ability to establish new plants and grow rapidly under a wide variety of site conditions.

-  the ability to disperse wide distances, often by the spreading of vegetative fragments as well as seeds.

-  the lack of the natural controls on growth and reproduction that would be found where the invader is native.

What is the impact of invasive plants on the environment?

In minimally-managed areas, invasive plants crowd out native plants. The presence of invasive plants alters the way plants, animals, soil, and water interact within native ecosystems, often causing harm to other species in addition to the plants that have been crowded out.

​Invasive plants deny food and shelter to native insects, pollinators, birds and wildlife which have a symbiotic relationship with native plants developed over centuries. Invasive plants are considered second only to habitat loss as a major factor in the decline of native species.

Invasive, non-native species are considered on the  greatest threats to our environment. The damage they have already caused to natural ecosystems and the economy has cost governments, private land trusts, and landowners billions of dollars each year.

Control methods vary from mechanical (physical removal, introduction of fire or flooding), chemical (using herbicides), or biological (introduction of a natural enemy or pest which in turn requires continued monitoring of the introduced control). No method is fool-proof and the use of pesticides carries its own risks.