Plant of the Week
Vasey’s Trillium (Trillium vaseyi) Harbison
By Mark Pistrang
Based upon recent genetic research trillium species have been removed from the family Trilliaceae and placed back in the Liliaceae. Trilliums are rhizomatous herbs with unbranched stems. Trillium plants produce no true leaves or stems above ground. The “stem” is actually just an extension of the horizontal rhizome and produces small, scale-like leaves called cataphylls. These highly modified leaves surround the flowering scape (the above ground plant) as it pushes up through soil in early spring. The leaf-like structures are technically bracts subtending the flower. Despite their morphological origins, the bracts have external and internal structure similar to that of a leaf, function in photosynthesis, and most authors refer to them as leaves.
Trilliums are divided into two major groups, pedicellate and sessile trilliums. In the pedicellate trilliums, the flower sits upon a pedicel (stalk) that extends from the whorl of bracts. These trillium flowers are either “erect,” above the bracts, or “nodding,” recurved under the bracts. In the sessile trilliums there is no pedicel and the flower appears to arise directly from the bracts.
Vasey’s trillium is a perennial herb that blooms from April to May. The inflorescence is quite showy, yet easily overlooked as it is recurved under the large spreading leaves.
This plant is typically found on very rich soils of slopes and coves over mafic or calcareous rock, often in or near seepage areas.
Vasey’s trillium is native to the southeastern United States, southern Appalachian Mountains (Virginia, North Carolina, Tennessee, South Carolina, Georgia, and Alabama). It is not considered to be a rare species, yet like other trilliums is vulnerable to land-use conversion and habitat fragmentation.
For More Information
- PLANTS Profile - Trillium vaseyi, Vasey’s Trillium
- Trillium vaseyi in Flora North America.
- Case, Jr., Frederick W., Roberta B. Case. 1997. Trilliums. 285 p. Timber Press, Portland, OR.
- Jacobs, Don L. and Rob. L. Jacobs. 1997. Trilliums in Woodland and Garden: American Treasure. 152 p. Eco-Gardens, Decatur, GA.