Lactarius xanthogalactus (Yellow-staining milk cap)

Lactarius xanthogalactus, commonly known as the yellow-staining milkcap is a poisonous species of fungus in the family Russulaceae. It produces mushrooms with pinkish-cinnamon caps up to 11 cm (4.3 in) wide held by pinkish-white stems up to 6 cm (2.4 in) long. When it is cut or injured, the mushroom oozes a white latex that rapidly turns bright sulfur-yellow. The species is found on the west coast of the United States and grows in the ground in association with hardwood…

— Wikipedia