Camas is a species of edible plant found in the Pacific northwest. The natives in the area prized its root for its sweet flavor, somewhat between a pumpkin and a sweet potato. This plant famously saved the Lewis and Clark expedition from starvation.
However, I must note that Tualitin Hills Nature Park discourages visitors from eating plants found growing within the park!
Link
Velantian
Yeah, eating plants unfamiliar to you can be hazardous.