Plant of the Week
Snow Trillium (Trillium nivale)
By Larry Stritch
The snow trillium is an herbaceous, long-lived, woodland, perennial wildflower with a limited distribution in the Midwestern states of Iowa, Minnesota, Wisconsin, Illinois, Indiana, and Ohio with outlier occurrences in South Dakota, Nebraska, Michigan, Kentucky, Maryland, Pennsylvania, Virginia, and West Virginia.
Snow trillium is truly a harbinger of spring with occasional late winter appearances in March while snow is still on the ground. Snow trillium is never common and can be very rare often with local occurrences in many parts of its range. Within some of these local occurrences very large, dense populations do occur.
Trillium nivale: Trillium, from the Latin tri, refers to the flower parts occurring in threes, and llium from the Latin liliaceous, refers to the funnel-shaped flower. Nivale, from the Latin nivalis, pertains to snow, referring to its occasional flowering while there is still snow on the ground.
Trillium nivale is very dwarfed, with a short, thick rhizome from which a sheath (cataphyll) enclosed scape (stalk of the inflorescence) emerges from the ground to 3 to 5 cm tall with a single, terminal flower on an erect, becoming strongly recurved (when in fruit) pedicel, 1 to 2 cm long; leaves (actually bracts) three, dark green, definitely petioled, elliptic-ovate or ovate, obtuse to slightly acuminate, 1.5 to 5 cm long; petals three, white, very showy, recurved to erect, elliptic-ovate or ovate, obtuse to slightly acuminate, 1.5 to 4 cm long, recurved at the middle to form a very funnel-shaped corolla; sepals three, green, spreading, shorter than the petals; fruit a berry, green, indented-globose; brown seeds.
Trillium nivale flowers from mid-March to early April. The species occurs in a range of habitats in limestone-derived soils, calcareous glacial drift or loess deposits. Snow trilliums occur in two different niche habitats that explains there sporadic occurrences. In one habitat, they grow on limestone crevices, limestone talus slopes, bare, sliding soils on the top of limestone cliffs and very steep loess deposits. In these habitats, the soils are sparsely vegetated, if at all with no accumulating organic matter such as leaf mold and litter. In snow trillium’s other niche, it occurs on floodplains at the highest points of flooding were the substrate is gravely or sandy and not packed clay soils and generally calcareous.
For More Information
- PLANTS Profile - Trillium nivale, snow trillium
- Case, F. W. and R. B. Case. 1997. Trilliums. 284 pp. Timber Press. Portland, Oregon.
- Jacobs, D. L. and Jacobs R. L. 1997. Trilliums in Woodland and Garden: American Treasures. 152 pp. Eco-Gardens. Decatur, Georgia.
- Patrick, T. 2007. Trilliums of Georgia. Tipularia 22: 3-22. Georgia Botanical Society.
- Frett, J. 2007. Trilliums at Mt. Cuba Center: A Visitor’s Guide. 75 pp. Mt. Cuba Center, Inc. Greenville, Delaware.