Invasive toxic, self-cloning hammerhead worms are spreading in Tennessee. The worms, which are native to Japan and Korea, made their way to the United States on the soil of ornamental plants, and have now moved throughout the country through the movement of soils, especially in greenhouse production, and have been spotted in several Eastern Tennessee counties recently. The worms are anywhere from four to 15 inches long and secrete chemicals through their skin which can cause skin irritation in humans. They are harmful not only to plants but also to essential earthworms and animals. Here’s the scary part… If you try to cut one in half – the most common way to kill a worm – it will just regrow into two separate worms. Individual flatworms can be killed by placing them in alcohol or into a bag and freezing them.