Lily family (Liliaceae)
Description: This introduced perennial plant consists of 2 leaves that are nearly basal and a single raceme of flowers. The leaves are up to 9" long, 4" across, and more or less erect; they are dark green, oval-ovate, smooth along the margins, and hairless. The veins of the leaves are parallel. The leaf bases are attached to a short basal stalk with several sheaths. The raceme of flowers is shorter than leaves (about 6" tall) and tends to nod at its apex; there are about 6-14 flowers per raceme. The flowers usually nod downward along one side of the raceme from slender pedicels about ½" long. Both the central stalk and pedicels of the raceme are green and hairless. Each flower has a bell-shaped white corolla up to 1/3" long and across; along the outer rim of this corolla are 6 short lobes that curve outward. Within the corolla, there are 6 stamens with short filaments and a single style with a tripartite stigma. The ovary has 3 cells. The blooming period occurs from late spring to early summer and lasts about 3 weeks. The flowers are quite fragrant. Fertile flowers develop into red berries up to 1/3" across that are globoid in shape. The interior of each berry is juicy and contains several seeds. In North America, most flowers fail to produce berries. The root system is fibrous and rhizomatous. Dense colonies of vegetative plants are produced from the rhizomes; these colonies tend to exclude other species of plants.
Cultivation: The preference is dappled sunlight to medium shade, moist to mesic conditions, and a rich loamy soil. Once it becomes established, this plant is long-lived and spreads slowly via its rhizomes.
Range & Habitat: Lily-of-the-Valley has escaped from cultivation primarily in NE Illinois (see Distribution Map), where it is uncommon in natural areas. This species was introduced to the United States from Europe as a horticultural plant; it is often grown in gardens because of the attractive foliage and flowers. According to some authorities, there is a native form of Lily-of-the-Valley in the region of the Appalachian mountains, although it cultivated less often than the European form. In Illinois, habitats include an upland area of a tamarack bog, rich deciduous woodlands, cemetery prairies, oak savannas near cemetery prairies, and former homestead sites. At some of these habitats, Lily-of-the-Valley was deliberately introduced and has persisted for several decades, notwithstanding long neglect.
Faunal Associations: According to Müller (1873/1883), honeybees collect pollen from the flowers; he was uncertain if nectar was produced by the flowers. The leaves are eaten by an accidentally introduced insect, Lilioceris lilii (Lily Leaf Beetle). This beetle has been found along the NE coast of the United States and may expand its range westward. Because the berries are not often produced in North America, it is not known which birds will eat them; the berries have been eaten by the Eastern Chipmunk, however. All parts of this plant contain cardiac glycosides that are toxic; therefore, its foliage is left alone by mammalian herbivores. Overall, the ecological value of Lily-of-the-Valley to wildlife appears to be low.
Photographic Location: A wooded area at Meadowbrook Park in Urbana, Illinois.
Comments: In addition to its cultivation in gardens, Lily-of-the-Valley has economic significance in the perfume and pharmaceutical industries. For the latter, it has been used as a source of heart medication. This species is listed in the Weedy Wildflower section because it is introduced, rather than native, and sometimes persists in natural habitats, particularly when there is some history of disturbance. Identification of this species is easy during the blooming period because of its distinctive racemes of flowers.