This is a piece of Ambrosia Maple that was taken down during a home renovation. This tree was close to 200 years old and was diseased. The ambrosia is an insect that bores holes in the tree and forms tunnels. The adults and white grub-like larvae do not eat wood. Rather, they feed on a fungus ("ambrosia") that grows in the tunnels. Fungus spores are carried by the beetles and introduced into the wood during tunnel construction. As the fungus grows, it discolors or stains the wood immediately adjacent to the tunnel. In some instances, the wood is stained for several inches above and below the tunnel.