When I was a youth many roads and streets were lined by towering American elm trees, but during the 1950s and Ď60s an invasive disease called Dutch Elm Disease (DED) began killing them. Scientists believe that the fungus that causes DED originally came from the Himalayas.† It travelled to Europe from the Dutch East Indies in the late 1800s. In the 1930s, the disease spread to North America on wooden crates made with infected elm wood. Today itís rare to find a native elm still alive and growing.
In 2007, the initial news media and study claims about manmade global warming versus natural climate change debates caught the publicís attention. And that debate remains ongoing. In 2008 US voters went to the polls and voted for change, but now some are having second thoughts as they live the changes being made. However, far less publicized was what is happening to our indigenous ecosystems as literally hoards of invasives have declared war on many of them. In the process we are very apt to see major changes in what weíre accustomed to seeing in our outdoor world.
Beginning in the 16th century, farmers in North America introduced wheat, rice, soybeans and cattle, among other imports, which today make up huge portions of U.S. food production. However, some non-native arrivals have been devastating. Gypsy moths, brought to Massachusetts in 1869 by a would-be silk farmer, managed to escape, reproduce and strip the leaves from millions of acres of forest. Descendants of some 100 starlings unleashed in New York City in 1890 now number 200 million, crowding out native birds from coast to coast. The Japanese vine kudzu was transplanted to the U.S. to prevent erosion; it has since run roughshod over 10 million acres in the Southeast.