Joe: Much of the earthworm literature states that earthworms were removed from the northern states by glaciers and that the worms never returned, and/or that North American species of earthworms can't live in glaciated areas.
However, there is no evidence for those statements. I have never seen any proof that earthworms lived in the north prior to the last glaciation, or that it takes more than 12,000 years for the earthworms to move about 1200 miles from the areas where they would have lived during the peak of glaciation, to places like MA, NH and MN. So, I think that they essentially reached the limit imposed by colder climates as they moved north. The correlations between whether an area is glaciated and native earthworms are present also does not hold up very well. Southwestern WI, for example, was not glaciated and has no native earthworm, whereas Southeastern WI was glaciated and does have two species of native earthworms. In addition to that, tundra and boreal forest with permafrost would have extended as far south as TN and NC at the peak of the last glaciation, and no North American earthworm species would find those habitats suitable, so they had to move a great distance just to make it back to places like MA and WI. I think earthworm ecologists are not very good paleoecologists, and look at the world as static, leading to their misinterpretation of glaciation versus earthworm presence. Lee Joseph Zorzin wrote: > Lee, to what extent is the lack of many native species due to a > slow rebound from the end of last glaciation? > Joe > > ----- Original Message ----- > *From:* Lee Frelich <mailto:[email protected]> > *To:* [email protected] <mailto:[email protected]> > *Sent:* Friday, August 07, 2009 9:59 AM > *Subject:* [ENTS] Re: earthworms and invasive plants > > > Joe > > Most of the earthworms you see at your latitude are European species, > The nightcrawler (Lumbricus terrestris), leaf worm (L. rubellus), > angleworms (several species of Aporrectodea and Octolasion), and > small > litter worm (Dendrobaena octeadra) are common European species > from the > Great Lakes through most of New England. You may also have some > Asian > worms (Amynthas species). > > Native earthworms are not very abundant in MA. They have a spotty > distribution and include the genera Eisenoides and the aquatic > Sparganophilus. > > I noticed a report that you also have the introduced earthworm > predator, > a flatworm named Bipalium adventitium. We don't know much about > it, or > whether it might control invasive earthworm populations, but it > recently > reached the Midwest as well. Its basically a small version of the > creature from the movie "Aliens". It squirts an earthworm with > acid/digestive juices and the earthworm dissolves, and the > flatworm suck > up the resulting dissolved proteins. Good thing its only 2 inches > long. > > Lee > > Joseph Zorzin wrote: > > Lee, which earthworms that we have in the east are not native? Does > > that include the common earthworm that is found in the NE? > > Joe > > > > ----- Original Message ----- > > *From:* Lee Frelich <mailto:[email protected]> > > *To:* [email protected] > <mailto:[email protected]> > <mailto:[email protected]> > > *Sent:* Friday, August 07, 2009 9:04 AM > > *Subject:* [ENTS] Re: earthworms and invasive plants > > > > > > Russ: > > > > Thanks--I was aware that the article was going to be published > > because I > > was one of the peer reviewers. I downloaded a pdf of it and will > > send to > > your e-mail address. > > > > We have known that invasive plants are facilitated by earthworms > > for a > > few years, but it is difficult field work to do to prove it. I > > suspect > > there will be several more papers on this topic in the next few > > years. > > In this case, the study shows that European earthworms > facilitate > > invasion of Japanese stiltgrass, barberry and garlic mustard. I > > suspect > > the worms also facilitate buckthorn and tatarian honeysuckle. > > > > Lee > > > > [email protected] <mailto:[email protected]> > <mailto:[email protected]> wrote: > > > ENTS....Lee: > > > > > > This is a link to a study of earthworms and invasive plants. > > > > > > I don't want to pay the $59 to read the entire article but > > someone in > > > the list might even subscribe to the publication it is > printed in. > > > > > > > > > > http://www.ingentaconnect.com/content/bsc/cbi/2009/00000023/00000004/art00029 > > > > > > Russ > > > > > > > > > > > > > > > > > > --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -~----------~----~----~----~------~----~------~--~---
