There are no native Yucca spp. in Illinois. At present, Yucca smalliana (Yucca) is the only species in this genus that has naturalized within the state. This plant has an unstable taxonomic history, and is sometimes referred to as Yucca filamentosa, Yucca filamentosa smalliana, and Yucca flaccida. Instead of the Agave family, it is sometimes placed within the Lily family (Liliaceae). It also has several common names, including Spanish Bayonet and Adam's Needle. A similar species, Yucca glauca (Soapweed), could be cultivated in Illinois as it is found in the Great Plains as far north as Nebraska and Iowa. It differs from Yucca in having a spike-like raceme of flowers, rather than a panicle, and its greenish white flowers are slightly larger in size. There are several other species of Yucca along the coastal southeast and desert southwest, but it is doubtful that they could survive our cold winters.