On page 11 of the Dec. 12 issue of the Mountain Democrat, the spongy, yellow fungus shown growing on Incense Cedar is a wood decay organism with the scientific name of Oligoporus amarus.
It causes what is commonly referred to as “pocket dry rot of Incense Cedar.” It occurs throughout the range of Incense Cedar, and frequently found in older growth trees. The fungus causes extensive pockets of decay in the heartwood, and often renders the tree
unmerchantable. Trees survive many years with the rot, and remain structurally sound. For more information see: Pests of California Conifer, David Wood and others, University California Press.