Trilliums and Wakerobins East of the Cascade Mountains of Oregon and Washington
The Genus Trillium
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Western Wake Robin: Trillium ovatum
Pacific Trillium, Western Wake-robin, Western Trillium: Trillium
ovatum (Synonym: Trillium ovatum var. ovatum) - Petals white. Flowers on peduncles. Leaves sessile.
Idaho Trillium, Petiled Wakerobin, Purple Trillium, Purple Wakerobin, Round-leaved Wake-robin: Trillium petiolatum: Petals maroon. Flowers sessile. Leaves with
petioles.
Paul Slichter