You might be harboring a noxious weed disguised as a pretty plant. Myrtle spurge (Euphorbia myrsinites), also known as donkey tail spurge, was once planted as a waterwise ornamental plant but has escaped from the confines of the garden to become a List A noxious weed. The Colorado Department of Agriculture, through a legislative process, declares plants noxious weeds when they become invasive and threaten either wildlands or agriculture. Myrtle spurge reduces habitat for native plants and the pollinators and other animals that depend on them. Because myrtle spurge is found in the wild in relatively small populations, there’s still an opportunity to keep the plant from spreading out of control (unlike in Utah, where it covers thousands of acres). List A weeds are subject to eradication wherever they’re found, regardless of land ownership (including private properties).