Trillium albidum

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....read more on Wikipedia.