Information from the Northwest Cook County Sierra
The phrase “exotic species” might sound
mysterious or romantic, but to the native plants of Illinois,
these outsiders offer nothing but a one-way ticket to
extinction. Exotic or invasive species are those forms of plant
or animal life that are not part of an established ecosystem.
Exotic species tend to crowd out native species, often
destroying the native ecosystem in the process.
Here in northern Illinois, exotic species such as
Buckthorn took hold in fertile soil and have become a serious
threat to our native ecosystems. They grow in our natural
areas, and they pop up consistently in our backyards— crowding
out trees, brush, grass and natural yard lines. Buckthorn tends
to produce leaves well before our native trees and shrubs. This
lets the exotic Buckthorn begin growing before the native plants
even wake up for the spring. And, those fast growing leaves of
Buckthorn shade the natives, taking away the vital sunlight that
promotes healthy growth.
Buckthorn can be cut back and destroyed in early
spring and late fall. It is easy to identify since it develops
leaves earlier than natives and keeps those green leaves growing
long after most native trees have dropped colorful fall leaves
to the ground.
Many exotic invasive species got their start when
introduced into gardens by property owners. If you are planning
a garden project, use an abundance of native. You’ll be
surprised how many beautiful, indigenous flowers and grasses
graced the prairies of Illinois.
Although six varieties of Buckthorn have been
illegal in Illinois since 2003, preexisting growth continues to
cause extensive damage and threaten the ecology of our area.
You can help control and growth and spread of this exotic
invasive species in a number of ways.
First, be on the lookout for it in your own
backyard. Also, the Sierra Club promotes outdoor workdays here
in Cook County’s northwest suburbs, including our own nearby
forest preserve. You’ll learn to identify the exotic invasive
species, how to control their invasive nature, and you’ll be
able to see the difference you’ve made right away. The
information you learn may someday help your own yard. A few
hours of your time in the spring and fall can make a difference!
Sierra Club web site
Department of Natural Resources web site