Trillium albidum J.D.Freeman

 

Trillium albidum is a species of flowering plant in the bunchflower family Melanthiaceae. It is the only trillium characterized by a stalkless white flower. The species is endemic to the western United States, ranging from central California through Oregon to southwestern Washington. In the San Francisco Bay Area, it is often confused with a white-flowered form of Trillium chloropetalum. In northern Oregon and southwestern Washington, it has a smaller, less conspicuous flower.

Trillium albidum was first described by John Daniel Freeman in 1975. The specific epithet albidum means "white", a reference to the uniformly white flower color of this distinctive species. It is commonly known as the giant white wakerobin or white toadshade.

Description

Trillium albidum is a perennial herbaceous plant that persists by means of underground rhizomes. There are three large leaf-like bracts arranged in a whorl about a scape that rises directly from the rhizome, growing to 22 to 58 cm (8.5 to 23 in) in height. The bracts are sessile and broadly ovate, each 10 to 20 cm (4 to 8 in) long and 12 to 15 cm (4.5 to 6 in) wide. The bracts are green and weakly mottled with brown or dark green spots (which often fade later in the season).

Each stem produces one flower, which is held on top of the bracts. The fragrant flower has three lance-shaped green sepals and three wider white (sometimes pink or purple-tinged) petals measuring 4.8 to 8 cm (2 to 3 in) long and 2.2 to 3 cm (1 to 1 in) wide (although there is a conspicuously small-flowered subspecies as noted in the previous section).

Trillium albidum subsp. albidum and T. albidum subsp. parviflorum are distinguished on the basis of multiple characters:

Trillium albidum - Wikipedia