Another article on this topic. The Westchester section of the Sunday New York Times. Good general background but a focus - as you might expect - on the NY suburbs, Especially the spread north from NYC specifically the Bronx where the issue was studied at NYBG. It is a logical spread as Westchester is immediately adjoining to the north with a number of greenway cooridors providing the link.
For those of us who don't see these publications, can you give a little more of a synopsis on the subject? Are you saying there is an ecological problem due to introduction of exotic species?
-Mark (in N. California)
It seems that 10-15000 years ago the last ice age (the Pliestocene I think) covered the continent with ice as far south as say NJ. That wioed out all the native earthworms (as well as cads of other species). Over the thousands of years following the forests crept back in. And they evolved in the absence mostly of earthworms which crawl quite slowly(you might have noticed). The northern forest ecosystem included a rich and thick "duff: layer. Outside the range of the ice native worms survived. (Including our night crawlers) They burrow into the ground during they day. Emerge at night and drag food to the burrow. Crawl back in an eat it and sleep during the day. They shop locally and stay at home much more than they traevl. I'm not entirely clear on this point becasue none of the sources are clear.... but I guess that the tree that re-populated the northern lands after the glaciers retreated were evovled with these native worms.
In colnial times the Uropeans brought their worms with them. These worms colonized the northern forests. Not too big a problem. But in the late 20th centuryAsian worms have gotten in, probably in soil with importd Asian plants.
The Asian worm do not burrow, They feed and live on the surface. And they eat everthing. The duff layer can be completelyconsumed. The ecology of the forest floor is changing. Loss of forest floor plants including seedlings of the large trees. Loss of invertabrates. Loss of fungi. Increased soil temps. Prognoisis
There is quite an extensive University of Minnisota web site on this problem. It should pop if you do a search/
And I still get this funny character set Russ. So I canno tell exactly what I have typed.
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