The alien earthworm invasion is here, says new study
There's been a takeover of North America's soil by scores of non-native earthworm species this past century. It's time we pay more attention to the invaders and their potentially major impact on the continent's ecosystem, says a new Stanford study.Since the late 1800s people have been importing earthworms to the shores of the Americas from nearly every other continent in order to bolster farms and gardens. The worms help in this regard because they make tunnels that allow water, nutrients, and air to penetrate the soil…