Death Camas (Zigadenus venenosus)
Aliases: Meadow Deathcamas
No matter how much they beg you, don't let your livestock accompany you to Yosemite and graze on Death Camas. It's pure poison from tip to toe, and sampling its delicate shoots will be their last happy act. Don't eat it yourself, either, for that matter.
Blooms: May - August
Size: Generally 1 - 2 feet (25 - 50 cm) high on a single stem accompanied by long, slender leaves up to a foot and a half long.
Zigadenus venenosus etymology: Zigadenus derives from the Greek word for yoke, and refers to the shape of the gland on some members of the genus. Venenosus derives from the Latin word for poison.
This Photo: Near the western shore of Bass Lake, late May. Inside Yosemite, I've seen it along the Wapama Falls and Wawona Meadow trails, and it's also reputed to grow in Yosemite Valley.
Other Resources: CalFlora · CalPhotos · USDA · eFloras.org · fed.us