Three boring insects

BORERS ( LONG-HORNED BEETLES AND OTHER BEETLE BORERS) Borers that attack evergreen trees are primarily long-horned beetles (round headed borers).  These beetles are an inch or more with long antennae.  Other beetle borers include bark beetles and metallic wood borers such as the bronze birch borer or the flatheaded appletree borer.Symptoms include branch dieback due to feeding damage, and exit holes. Exit holes of long horned beetles are oval and about 1/4 inch or larger in diameter.  There are many different types of boring insects that attack a large range of plants.The best control for bark beetles and borers is prevention. Healthy trees are able to withstand most bark beetle and borer attacks.  Insecticidal sprays will not kill the beetles or larvae inside the tree and sprays will not reverse the damage that has already occurred.  Trees should receive adequate water in times of summer drought. Dead or dying trees should be removed to eliminate breeding sites for additional beetle generations.  

CATERPILLAR BORERS - Caterpillar borers include carpenter worms, and clearwing borers such as peach tree, lesser peach tree, dogwood and lilac/ash tree borers.  Larvae of these borers are creamy colored with brown heads and the adults are moths.Signs of damage include holes in the bark, reddish sawdust in bark crevices or around the bottom of the tree and branch dieback. In flowering cherries, the peach tree and lesser peach tree borer may cause the tree to leak a gummy substance at entrance and exit holes.  We have seen branches killed in some of our cherry trees because of borer feeding damage.  At Morris Arboretum, traps are used to monitor these pests by capturing the flying adult insects.  We have caught lesser peachtree borers, peachtree borers, ash/lilac borers, and rhododendron borers.Keep trees well watered during dry periods because these pests prefer to feed on and lay their larvae in stressed trees.  Avoid wounding the trees with lawn mowers and string trimmers.  To help prevent borers, especially in cherry trees, keep mulch away from the base of the tree to prevent making a good habitat for the pests.