Erythronium montanum, the Avalanche lily.
A genus of Eurasian and North American plants in the lily family.
https://en.wikipedia.org/wiki/Erythronium_montanum

Trillium " Trillium albidum"
https://en.wikipedia.org/wiki/Trillium and/or https://en.wikipedia.org/wiki/Trillium_albidum
Trillium (trillium, wakerobin, toadshade, tri flower, birthroot, birthwort, and sometimes "wood lily") is a genus of about fifty flowering plant species in the family Melanthiaceae. Trillium species are native to temperate regions of North America and Asia,[3][4] with the greatest diversity of species found in the southern Appalachian Mountains in the southeastern United States.
(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.)
In the region between Corvallis, Oregon and the Columbia River, the species is variable and difficult to identify to subspecies level. The directional arrows in the table above point toward the subspecies that dominates with respect to that character.[7]

Trillium albidum is the only sessile-flowered Trillium species characterized by white flowers. Throughout most of its range, this characteristic is sufficient to identify the species, but in the San Francisco Bay Area where both T. albidum and a white-flowered variety of T. chloropetalum occur, the two species are distinguished by their reproductive organs. The latter has dark purple stamens and carpels while those of T. albidum are almost invariably white or pale green, with occasional purple stain.
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