Cow parsnip (Heracleum lanatum), closeup of many umbel flowerheads, showing the umbellets of flowers from underneath for the top umbels.  At 8900ft along High Trail (part of Pacific Crest Trail) above Agnew Meadows, Ansel Adams Wilderness, California.
<a href="//commons.wikimedia.org/wiki/User:Dcrjsr" title="User:Dcrjsr">Dcrjsr</a>
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>