Sometimes, introducing exotic plants and animals into a habitat is
the equivalent of throwing a wrench into the cogs of a machine: In some
cases, the machine continues to operate, but at a much-reduced
efficiency. In other cases, the machine shuts down completely.
Exotic
— also called “invasive” — species are nothing new. A variety of
animals and plants has been introduced to North America in the 500-plus
years that the continent has been explored, settled and developed.
Some
were introduced on purpose, others by accident. These introduced
species are collectively known as “exotic” species because they’re not
indigenous to North America. The opposite of exotic is “native.” Native
species are the plants and animals that were the original inhabitants of
our landscape.
Some
exotic plants such as kudzu and fescue are well-known to people, but
there are many others. Some have become so common that we don’t realize
they’re not from around here.
Take,
for instance, the two most common types of crabgrass found in
Midwestern yards (and the types you’re probably trying to get rid of in
yours) — hairy crabgrass (Digitaria sanguinalis) and smooth crabgrass
(Digitaria ischaemum). Neither is native to North America: They were
introduced here, probably in the 19th century.
On
the animal side, zebra mussels and Asian carp are highly publicized
exotics that have made the news as threats to aquatic habitats in parts
of the United States.
Gypsy
moths and emerald ash borers are well-known non-native tree pests that
pose both habitat and financial threats to forests in the eastern and
central parts of the country.
One of our less-publicized exotic animals is the house mouse (Mus musculus).
This
common pest, which is the mouse species we commonly encounter in homes
and other domestic dwellings, wasn’t here when Europeans arrived. It
had numerous introductions to North America via the ships of explorers
and colonists.
Though
the exotic species that have come here are varied, the reasons they’ve
become abundant are similar: Exotic species were introduced into areas
that had none of the natural controls (browsing animals, predators,
harsher weather, etc.) that kept them in line in their native lands,
and, as a result, these newcomers flourished.
This abundance has often come at the expense of native plants that formed the foundation of our habitats.
When
exotic species invade an area and crowd out the plants and animals that
occurred naturally in that location, habitats often change for the
worse: The insects that were attracted to native flowers go elsewhere,
the native birds can’t find nesting areas because they’re occupied by
exotic birds and other animals that needed these species for some part
of their life cycles are also negatively affected.
Wise
conservation practices using native species pay by enriching our
economy and quality of life. Conversely, exotic invasions can have
negative financial repercussions.
Gypsy
moths and emerald ash borers are already having an effect on the timber
industry. When exotic plants such as musk thistle, spotted knapweed or
Johnson grass take over pastures and fields, they can turn what had been
money-making acres into financially unproductive tracts of land.
As always Servall Termite & Pest Control is here for all of your pest control and home repair needs. Contact us today at one of our four convenient locations or visit http://www.servallpestcontrol.com!
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