Mystery fungus no longer!

The fungus pictured yesterday has been identified by Sunkat as Hericium erinaceus, also known she says as:

• pompom
• lion's mane
• monkey head
• old man's beard
• bearded shelf
• bearded tooth
• hedgehog

She also says it's "very edible when young, medicinal."

I found a glorious photograph at a website that says it's "a California fungus."

Mystery fungus

Can you identify this fungus? I took the photograph on December 31, in the woods down in back. The fungus was growing on an oak tree about six feet off the ground. It's about 5.5 inches from top to bottom.