While the major damage caused by the Asian Longhorned Beetle occurs when the larvae of this insect bore into the wood of tree trunks and branches, adult beetles do feed on the leaves and twigs of their host plants. Rather than cutting circular or oval holes in leaves, like many other beetles, the ALB tears away at the veins of the leaf, creating jagged holes:
Note how the beetle strips off the outer tissue of the twigs. Similar damage can also be seen on leaf stems. This type of feeding often causes early leaf drop, so look for signs of feeding damage on leaves that are on the ground below the tree.
(Photos courtesy of Michael T. Smith, USDA-ARS)