Exotic, Invasive Earthworms: A Clear and Present Danger to Regeneration in Our Northeastern Sugarbushes Bruce L. Parker & Margaret Skinner The University of Vermont, Entomology Research Laboratory 661 Spear Street, Burlington, VT 05405�0105 Contact Information: bparker@uvm.edu Tel: 802:656-5440
& Josef GÓ§rres The University of Vermont, Plant and Soil Science Department 258 Jeffords Hall, Burlington, VT 05405
This proposal addresses an emerging Maple Syrup industry issue: Management of exotic annelid worms, an invasive pest threating sugarbush forest health.
Executive Summary. Historically earthworms have been perceived as indigenous native organisms that enhance soil fertility. Few realize they are exotic species, some of which are invasive and represent a serious threat to sugarbush health. These worms are disrupting the natural biodiversity by transforming the forest floor structure and chemistry by rapidly consuming the understory
Fig. 1. Hatchling Amynthas worm found in soil. They could be anywhere, and they are spreading everywhere.
leaf litter layer which prevents maple regeneration and reduces the fertility and moisture-holding capacity of sugarbush soil. New, particularly aggressive, more destructive East Asian earthworm species (genus Amynthas, a.k.a. Alabama Jumpers or Snake Worms) are colonizing our forests and sugarbushes (Fig. 1). 9,10,11 In the past these worms were mainly observed in warmer Southern climates, where they are used as bait and compost worms. 9 They have now spread to Vermont and other New England states. In areas where Amynthas has become established, the leaf litter is gone within a few months, leaving bare soil and survival of maple seedlings is limited (Fig. 2). One of the first places where they have been noticed was in sugarbush in Shelburne, VT, where the reduced abundance 1