PSHB is not able to complete its life cycle on all the tree species it attacks. Trees in which the beetle can breed and multiply are referred to as ‘reproductive host trees. Important reproductive hosts include species of oaks, maples, willows and coral trees, avocado, and castor bean. ‘Non-reproductive host trees’ are attacked by the beetle, but the beetles do not establish galleries (tunnels) or breed. The fungus may or may not cause disease. Trees are generally not expected to die. See Addendum A - Reproductive Trees and Addendum B - Non-Reproductive Trees.