Dieback of leaves that begins in the upper third of the tree and progresses downward over time.

(J. Ellis, Purdue University)

Vertical splits in the tree's bark.

(C. Sadof, Purdue University)

D-shaped exit holes that are only 1/8 inch wide found in the tree’s bark on the limbs and trunk, the result of the emergence of newly formed adults.

(J. Ellis, Purdue University)

S-shaped channels found under the tree’s bark caused by larval feeding.

(J. Ellis, Purdue University)

Heavy woodpecker activity that is especially noticeable during winter months

(D. Cappaert, MSU)

Water sprouts (epicormic shoots) that appear at the tree's trunk.

(J. Ellis, Purdue University)

Worm-like larvae (immatures) found under the tree’s bark that can grow up to 1-inch long.

(D. Cappaert, MSU)