Invasive worm Threatens forest floor
Invasive Specie of the Month….The Jumping Worm. Earthworms have been considered as a friend of the gardener for a long time with their ability to loosen and aerate the soil. But the story is changing in many parts of the country. There are invasive earthworms not native to North America that are causing damage to hardwood forests, such as those consisting of maple, basswood, red oak, poplar or birch species. Conifer-dominated forests seem to experience less dramatic impacts. The problem is that these invasive worms will consume the entire floor of organic matter in a forest. The earthworms come into an area with a thick leaf mat, and can consume it in as little as two to five years. In some parts of Great Smoky National Park, the ‘jumping worm’ population is so high there is almost no leaf litter left.
Species of invasive worms are well established in the Lake States, the Northeast, and Southeast.
Not all foreign earthworms are destructive. Of the 5,000 species of worms around the globe, only about 16 of the European and Asian varieties do the real damage. One of the most destructive invasive worms is called the Alabama jumper. It is also known as the snake worm or crazy worm. It is an aggressive Asian worm that lives in high numbers and can literally jump off the ground or out of your hand. These invasive worms are readily sold over the internet to the public for fish bait, composting, and as gardening aids. Worm ranching, or ‘vermicomposting’ is an emerging and lucrative business and is a big reason for the spread of these invasive species. The jumping worms are heavily marketed for their ability to process more food…and that is the problem. You can get even buy jumpers at Amazon or Ebay. A 1000 jumpers will cost you about $70 and you can buy them in quantities up to 10,000.
The presence of the earthworms affects more than just the plants. One example is that adult salamanders can consume these earthworms but the worms are too big for juvenile salamanders to eat, which leads to a net loss in salamander numbers. And these salamanders themselves are an important prey species for snakes, small mammals, turkeys and other animals.
Once established, earthworms are impossible to remove from the environment, The U.S. Department of Agriculture recently awarded grants to study the ecology of the earthworm invasions. Researchers agree that the best hope is to contain the worms, which spread only 15 to 30 feet a year on their own, but can travel thousands of miles in the mail.