Pleurotus, Redwood East Bay Regional Park, Oakland, California
Oyster mushroom (I think) on California laurel (Umbellularia californica). I am not a fungi expert so please me know if you disagree.
Pleurotus is a genus of gilled mushrooms which includes one of the most widely eaten mushrooms, P. ostreatus. Species of Pleurotus may be called oyster, abalone, or tree mushrooms, and are some of the most commonly cultivated edible mushrooms in the world.Pleurotus fungi have been used in mycoremediation of pollutants such as petroleum and polycyclic aromatic hydrocarbons.