When Jamestown, which did not have any earthworms before because of the most recent ice age, was introduced to these creatures, the place received healthy soil and appropriate conditions for agriculture. Earthworms created massive network of tunnels by eating through the soil beneath the ground, making it able to let in air and water. These two elements are required for healthier soil. Temperature in Virginia can make the earthworms “Turn over the upper foot of soil” every few decades, which made them ecological engineers who reshaped entire expenses.
The creatures can also clean up piles of leaves in a few months and insert castings or worm excrement filled with the leaves’ nutrients into the soil. This causes the trees and bushes in places where no earthworms are living, die. The trees and bushes depend on litter for food. So, if the earthworms take away the nutrients into the soil, the plants will be unable to find the litter. This makes the forest lose its understory, which are bushes and plants living underneath the main canopy of the forest. One of the understory plants are tree seedlings, that will prevent trees to grow after the main trees die