This is the somewhat rare Clubhair Mariposa Lily. It is known as a fire-follower, as it blooms in greater amounts in the years after a big wildfire - but even then it is still unusual. Notice the thin red jaggedy line, and the yellow hairs with little clubs on the ends of them. Calochortus clavatus (Lily family)

Those other yellow flowers are called Golden Yarrow - Eriophyllum confertiflorum (Sunflower family). They are much more common than the Lily.