Veratrum californicum, False Hellebore. Family Melanthiaceae. Common in marshy riparian zones. Rhizomes are extremely toxic. Veratrum contains highly toxic steroidal alkaloids that activate sodium ion channels and cause rapid cardiac failure and death if ingested.
Don't eat these.
Equisetum arvense, Horsetail, Scouring Rush. The only living genus from Family Equisetaceae, others are present in fossilized specimens. Ours are found in wet marshy areas. Early settlers in the Rocky Mountain region reputedly used the silica-laden stems to scour their pots and pans. Extracts have historically used for medicinal purposes, but I'd never eat this stuff.
The big leaves in the foreground are Thimbleberry.