Are you one of those folks that tiptoes down the sidewalk after a heavy rain to avoid squashing one of the hundreds of earthworms that crawl out of the soil? There's no need to worry — walk freely! Most of the worms in South Carolina are invasive species, anyway.
Most gardeners see earthworms as friends to their vegetable patch. The steady little workers eat, digest and poop out organic matter, speeding up the process of decomposition and naturally fertilizing the soil. As they crawl around under the surface doing their business, they also churn up the soil, like miniature plows, allowing oxygen to reach the plants and giving the roots rooms to grow.
So, it's understandable that instead of stomping through puddles in your brightly-colored galoshes, you tip-toe gingerly with your eyes glued to the sidewalk.
It is true that there are earthworms that are native to our area, unlike the northern states where all the worms were wiped out in the last ice age. However, with the invasion of the European variaties, the native worms are on the decline. It is rare that you will ever even find a native earthworm.
Both the European nightcrawler and Belgium red worms are sold in South Carolina for fishing bait and as a composting aid. Many times other species are labled and sold as "nightcrawlers" because worms are so difficult to identify.
So what? They aren't native but they seem to be doing good, not evil. No matter what the effect is that a non-native species seem to have on the environment, we should always be cautious. A classic example is that of kudzu. It was introduced to control erosion, but since its introduction, it has gone crazy!
Like kudzu, the exotic earthworms have taken over. They dominate most of the soil communities in our area.
Exotic earthworms have drastically changed the soil ecosystem, arguably the most important ecosystem on Earth. Consequently, earthworms have contributed to localized plant extinctions and changes in animal wildlife.
With exotic species, it is always best to send them back whence they came, because it is difficult to foresee the impact they will have on the environment.