For Release February 6, 2001

Beware the Alien Invaders!

by Chuck Otte, Geary County Extension Agent

I spent half a day in a training session last week that just scared the living daylights out of me! It was all about aliens. The presenters discussed the nasty details: how they get into our country and state, how they establish themselves, how humans actually help them and what kind of terrible damage they can do. Oh, Iím not talking about extra-terrestrials, Iím talking about plants, insects, and diseases that are not native to the United States or Kansas.

We have already seen the kind of damage that these aliens cause. Look at musk thistle, field bindweed, sericea lespedeza and Dutch elm disease for some local examples. You may have heard about the possible contamination with Gypsy Moth egg masses on Christmas trees from Michigan back around Christmas. This is one pest that we want to stall as long as possible from getting to Kansas. Where Dutch elm disease attacked just a couple species of trees, Gypsy Moth caterpillars will eat almost anything.

The most significant problem with nonnative species, is the lack of natural control. Anytime you move an organism out of itís native location to someplace new, one of three things will happen. It will die because itís not adapted to our climate. It will live, but not necessarily thrive. Both of these two possibilities are what usually happen and thatís okay. The third possibility is that the organism thrives because the natural checks and balances that existed in its native habitat or absent. Then you have a problem such as musk thistle.

The major mode of dispersal is humans. It is seldom intentional. It is often a pure accident. It sometimes even started off with good intentions. Kudzu was intentionally planted in the southeastern United States to stabilize the soil during the 1930s. In the absence of its natural controls, it has become a major pest.

What we are facing today is the shrinking of the world. True global trade is becoming closer and closer to reality. People travel more widely and the risk of something hitching a ride becomes a very real possibility. It isnít a case of IF creatures will get moved around the world, but rather a case of which ones and how much damage might we see.

Southern Florida is being overrun by nonnative plants. Many tropical species have been brought in for landscape purposes and have escaped to become major weeds. Even in Kansas we face risks. Purple Loosestrife is a lovely wetland loving plant that we often find in water gardens. Neighboring states to the north and east have had to declare Purple Loosestrife a noxious weed. Japanese Bloodgrass is a popular ornamental that is headed for the federal noxious weed list. Unfortunately, the urge to plant something different or unusual often overcomes common sense.

Many insects are being found in the wood of packing crates. Manufactured items are arriving from China, Russia and other countries that we havenít traded with before. Several different boring beetle insect pests have already arrived in this manner. The Asian Longhorned Beetle has been found in Chicago and New York. Thousands of street and park trees, in these cities,have been clear-cut in an effort to stop or eliminate this pest.

What can you do? A lot! If you see something that looks out of the ordinary, call me. Iíd rather have you call me about something that wasnít a problem than to not call me because you werenít sure. Donít move plants, especially outdoors landscape plants, from state to state without checking first. Many insect and weed pests are moved about this way. And when you landscape, try to stay with native species. Youíll probably have better luck and youíll be less likely to cause a problem. The aliens are out there, and theyíre just waiting to come to your neighborhood!


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