 The Illinois Department of Natural Resources Division of Natural
Heritage reports that animals and plants not native to Illinois at
the time of European settlement are considered exotic species. Many
species of exotic plants are harmless and very useful in windbreaks,
landscaping and in preventing erosion. However, some exotic species
do have the potential to invade natural communities and displace
highly desirable native plants. Such plants are invasive species.
Some invading plants have become so well established in many areas
throughout Illinois that they may be thought of as native species.
"Employees of local, county, state and federal agencies and hundreds
of volunteers throughout Illinois spend millions of dollars and
thousands of hours every year in attempts to eradicate, manage or
control invasive plants and animals on the ground and in our
waterways. The governor and conservation agencies and organizations
are working to make all Illinoisans aware of the impacts of invasive
species to Illinois' diverse landscape -- and the environmental and
economic costs we face if we lose the battle to control them," said
Marc Miller, director of the Department of Natural Resources.
Wildlife managers spend more time carefully manipulating the
physical and chemical environment of plants than in direct
management of game animals, since plants are the major component of
both the habitats and the health of animal populations is dependent
upon them. The invasion by exotic plant species can turn
high-quality habitat into degraded and undesirable habitat for
wildlife.
Management tools including biological controls, prescribed
burning, mowing, spraying and physically removing the plants by hand
are available but can be costly.
Increasing public awareness of invasive species is an essential
goal because prevention and early intervention are the most
effective and cost-efficient approaches to address the economic and
ecological effects of exotic invasive species.
To recognize invasive species management efforts in the state
during Illinois Invasive Species Awareness Month, the IDNR and
partner agencies presented the following awards in a May 1 ceremony
at the department headquarters in Springfield:
Karen Tharp, Professional of the Year: Karen Tharp is recognized
with this award for her work as volunteer steward network
coordinator and supervisor of the Southern Illinois Invasive Plant
Strike Team for The Nature Conservancy. Tharp has greatly influenced
invasive species efforts across the state of Illinois by organizing
herbicide trainings for volunteers in the Chicago region, helping to
start the New Invaders Watch and working closely with the Illinois
Department of Agriculture to develop the new amendment to the
Illinois Pesticide Act.
Illinois Department of Transportation Region 1, District 1,
Organization of the Year: IDOT Region 1, District 1 is recognized
with this award for revolutionizing the working relationship between
natural areas managers and transportation professionals. IDOT played
a pivotal role in supporting the development and establishment of
the Northeast Illinois Invasive Plant Partnership. IDOT is
conducting a multiyear invasive plant mapping, control and
monitoring project along its highways. In spring of 2011, IDOT began
to coordinate invasive plant control efforts along its rights of way
with the efforts of regional natural areas managers.
Greg White, Volunteer of the Year: Greg White has worked with the
Southern Illinois Weed Watch and has mapped invasive species at
several natural areas, often requiring him to endure heat, tough
climbs, mosquitoes and chiggers to finish his work. White also
assisted with the hand-pulling of Japanese stiltgrass along the
Rocky Bluff Trail at Crab Orchard National Wildlife Refuge and
helped the River to River Cooperative Weed Management Area in its
survey of bush honeysuckle at Trail of Tears State Forest.
For more information on Illinois invasive species awareness and
management efforts, go to
http://www.dnr.state.il.us/orc/invasive_species.htm.
Some invasive species facts from the Illinois Department of
Natural Resources:
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Invasive species
often invade and replace the native flora in a variety of ways
and will sometimes out-compete the native species to the extent
that the native plants totally disappear from an area.
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Garlic mustard and
the exotic buckthorns block needed sunlight, making it
impossible for many of the needed native species to survive and
reproduce. Such degraded habitats can quickly become a
monoculture of only garlic mustard or buckthorn, meaning no food
or shelter for native fish and game.
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Chemical toxins
inhibiting growth of all other plants nearby are produced by
garlic mustard and tree of heaven. These toxins are released
from their roots into the surrounding soil, thereby eliminating
competition from other plants for space, water and nutrients. In
some cases, the eliminated native species are very important
food plants for native game animals. Because of the extirpation
of many of native plants, a number of wild areas that once
supported healthy populations of deer, elk and other wildlife
are no longer prime habitat for the species in question.
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Bush honeysuckles
not only shade out most native plants, they also form such thick
stands of growth that hunters and anglers cannot walk through
the area or see game from a blind or tree stand. Multiflora
rose, with its strong thorns and tangled growth habit, forms
thickets even deer and turkeys find inhospitable for protection.
Such tangled growths of honeysuckle, multiflora rose and other
similar invasive plants often destroy the attractiveness of what
was once prime habitat for hunting, fishing, birding and
mushrooming.
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Chinese
bittersweet and porcelain berry grow to the tops of the tallest
trees in the forest, creating dense, smothering foliage -- and
the weight of the vines will eventually pull the trees down.
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Many undesirable
invasive species will compete more successfully than native
flora for water, minerals and other necessary nutrients, leading
to very poor growth of the native plants. Replacement of the
native flora with invasive species reduces the biodiversity of
the area since invasion by only one species often results in the
loss of several native species. This loss of biodiversity is of
major concern to ecologists both locally and globally.
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The fruit, seeds,
stems or leaves of some invasive plants are poisonous, or at
least result in illness when eaten. Leafy spurge can cause
blistering in the mouth and throat of livestock, including
horses, and is toxic if enough is consumed.
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Some invasive
plants are of considerable danger if humans make direct contact
with them. The juices of giant hogweed and wild parsnip cause
severe blistering of the skin of humans soon after contact with
the juice if exposed to direct sunlight. Scars from both of
these plants will be noticeable for several years. Tree of
heaven can cause intestinal and heart problems in people exposed
to its sap.
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Exotic plants are
introduced into new areas in a myriad of ways. The seeds of some
plants pass through the digestive systems of many animals,
including some birds, without being damaged. Some seeds are
widely scattered by wind before germinating in habitat suitable
for their growth and reproduction. Many of the smaller seeds,
such as garlic mustard, are so small they are carried in the fur
of raccoons, dogs, deer, horses and other animals, only to drop
off as the animals move into new habitat. Others, such as leafy
spurge and teasel seeds, collect on roadside mowers, only to
fall off farther down the road, accounting for the linear
distribution of some exotic plants along roads and railroad
rights of way.
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Oftentimes, people
trim plants growing in their yards and gardens without thinking
about proper disposal of the still-living cuttings that are then
dumped into an area where they take root. Cuttings, stem pieces
and rhizome fragments can be blown about or carried downhill in
runoff after a heavy rain before finding a new place to grow.
Kudzu, honeysuckles, periwinkle, English ivy and Chinese yam are
just a few examples of plants that have invaded new areas in
this manner.
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Many of today's
exotic invasive species, such as burning bush, wintercreeper,
periwinkle, Callery pear and the ornamental figs, were grown for
years before they exploded into the natural landscape and became
problems. Landscapers used more than 60 species of imported
ornamental figs in Florida for several decades without any
problems until the pollinating wasp for the laurel fig was
accidentally introduced about 20 years ago. The previously
sterile laurel fig then very quickly became aggressively
invasive, as it produced viable seeds that were easily
dispersed, giving it the necessary mechanism to invade the
surrounding natural areas and become a real problem. In some
cases, experts are uncertain why or how an exotic plant becomes
an invasive problem.
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For boaters and
anglers: a reminder that invasive fish, snails, plants, disease
and viruses can be transmitted by dumping bait or even just the
water from bait buckets, bilges, live wells, trailers and
equipment used on the water. Administrative rules in Illinois
prohibit the removal of natural water from waterways of the
state via bait bucket, live well, bait well, bilges or any other
method. Regulations also prohibit removal of any watercraft,
boat, boat trailer or other equipment from waters of the state
without emptying and draining any bait bucket, live well, bait
well, bilge any other compartment capable of holding natural
waters. Regulations also prohibit using wild-trapped fishes as
bait within the state of Illinois, other than in the waters
where they were legally taken. To protect Illinois waters,
inspect your boats and trailers for visible contamination of
plants, mud or water in bilges. By removing, cleaning or
draining the equipment, you help eliminate invasive species from
establishing in Illinois waters.
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An invasive species of significant
concern in Illinois is Asian carp. Unfortunately all four
species of Asian carp -- bighead, silver, grass and black carp
-- have been found in Illinois waters, likely escaping
aquaculture facilities of the southern U.S. Bighead and silver
carp are the focus of state, local and federal efforts to reduce
the populations and to keep this invasion from expanding into
other watersheds, such as the Great Lakes. For updates of the
Asian Carp Regional Coordinating Committee actions, check
http://asiancarp.us/.
[Text from
Illinois Department of
Natural Resources
file received from
the
Illinois Office of
Communication and Information] |
