More and more often, we hear about the arrival of a foreign plant or insect that is wreaking havoc on our native ecosystems. Take, for example, the Emerald Ash Borer, which will likely decimate all the ash trees in our forests.
If you want to see plants and animals from around the world, you don’t have to go to the zoo or botanical garden — just visit the Hudson River. When you get out of your car, you see common reed (phragmites), false-indigo and purple loosestrife growing along the edges of the parking lot.
Hemlock is a "foundation" tree species in eastern forests and its presence defines the properties of a unique ecosystem that is presently declining due to the introduction and spread of an invasive insect, the hemlock woolly adelgid.
Earthworms effect microbial nitrogen cycling and ecosystem nitrogen retention. Earthworm invasion of north temperate forests will have large consequences for nutrient retention and uptake in these ecosystems.