Damage by earthworms!

[Foremaple]

I just read an article about how earthworms are causing a tremendous amount of damage to northern forests as they are a invasive species here. They are great for crop soils but not forests. Are these claims true?

[WestfordSugarworks]

Yes. On some sites they are more of a problem than others. I do work as an invasive plant control contractor in the summer/fall and studied forestry here in VT in college. I work on one site right next to lake Champlain with a long ag history. Leaf litter gets consumed so quickly by earthworms that there is no duff layer. In some areas there is bare mineral soil by mid/late summer. Maples and other species which need the duff layer to keep adequate moisture and prevent seedling drying out cannot regenerate on these sites. Sugar maple will germinate and grow for one year but I’ve heard/seen that in their second year they often die out from dessication. Not much you can do about them. I think there is some research indicating that eradicating certain invasive plants will help reduce worm densities, but I don’t know as I haven’t read anything myself. We have abused our landscapes for decades and often find ourselves watching things drastically change many years beyond the point of a possible return to historic conditions.

[Michael Greer]

One of my small groups of trees grows in what was a backyard garden 50 years ago. The trees are only 40 to 50 years old, and mostly very healthy, but you can see the desiccated sandy soil which becomes pretty much bare by mid summer. I've been hauling leaves INTO that stand for the last five or six years in an effort to build a duff layer. Ask me in twenty years and I'll tell you how that worked out.