Crops Affected: Green Ash, Lilac, White Ash, Privet, Fringetree

States Affected: All states

Life Cycle: The adult female lays her eggs in crevices and loose bark on the host plant. After hatching, young larvae tunnel into the phloem tissue, feeding both horizontally and vertically. Overwintering occurs under the bark in their tunnels during the final instar. Pupation takes place in spring, near the bark's surface. Shed pupal skins are often visible after the insect emerges as an adult. There is one generation per year.

Damage: Lilac borers cause damage by tunneling and feeding in the sapwood of stems, branches, and trunks. The entrance holes and nearby ground accumulate light-colored, sawdust-like frass. Older lilacs are more vulnerable, with damage occurring to the trunk and larger branches. Dead canes at the center indicate lilac borer activity. Heavily infested trees can suffer branch dieback and mortality over multiple seasons. Visible holes and scars signal the insect's presence. Open-grown ash and trees in city landscaping are highly susceptible. The insect's activity also leads to to fungal infections by creating entry points for spores.

Season to Trap: March to June

How To Use: Hang trap with lure inside at shoulder height near at risk or affected crops. Replace lures every 30 days through the season, and replace traps when 70% saturated. Adult males are attracted to the pheromones in the lure and the color of the traps in this kit. Once they land on the sticky trap, they become ensnared, never to mate or lay eggs again.

Additional IPM Solutions: Avoid practices that destroy or disrupt native beneficial insects. Prevent mower injuries and other wounds to the trunk. Prune dead and dying lilac canes close to the ground, but avoid doing so during the moth flight period. Outside of this season, conduct renewal pruning by removing older branches near the base to discourage lilac borer activity and potentially boost flower production. Supplemental watering during drought periods can also protect hosts. If using pesticides like neem, permethrins, or spinosad, time application to target newly hatched larvae before they enter the plant, as controlling established larvae within the host is difficult.