Trillium ovatum

Trillium ovatum is a delicate and showy perennial flower of the early spring perched upon stems standing to 45cm and rooted by fleshy rhizomes. Triangular to oval shaped leaves are placed sessile in a whorl of three around the fleshy stem. The flowers are long lived and singly borne on the stalk tip composed of three green sepals, three petals white when young, turing a pinkish maroon with age, one might think they are variants of the same species. By late summer, an oval, green capsule with wing-like ridges, containing many seeds formed into a sticky, egg-shaped mass. Each seed has an oil rich appendage, called an elaiosome, that is attractive to ants, who carry the seeds back to their nest and eat only the elaiosome. Ants have been shown to disperse up to 30% of the spring flowering herbaceous species in the eastern North American deciduous forests while western North America is significatly less tied to ant dispersal. Trillium ovatum is a great example of a western species that requires the ants for dispersal.

T. ovatum is found in moist to wet coniferous woods, streambanks, shaded open areas at low to mid elevations. The geographic boundaries of T. ovatum include British Columbia southward to California, inland from the Coast to central California, southwestern Alberta, Montana, Colorado and Wyoming.

The flowers appear in the forests in March to May just as the Robins appear or ‘wake-up’ and are commonly referred to as ‘wake-robin’.

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References

Hitchcock, C.L. and A. Cronquist (1994) Flora of the Pacific Northwest, University of Washington Press, Seattle and London.

Kozloff, E.N. (1976) Plants and Animals of the Pacific Northwest. University of Washington Press, Seattle and London.

Pojar, J. and A. McKinnon (1994) Plants of the Pacific Northwest Coast. Lone Pine Publishing, Washington, Canada.

Venning, F.D. (1984) Wildflowers of North America: a guide to field identification. Golden Books Publishing Company, New York.

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