Name: Cerambycidae spp.

Alias: Longhorned beetles or roundheaded borers. These are not a single species, but an entire family of beetles that are distinct because of their long antennae which are usually longer than their body. They get the nickname of roundheaded borer because when they are done pupating, the adults exit the tree and leave a perfectly round hole, unlike other insects whose holes can have a distinct shape. Once the adults emerge, they do not re-enter the wood. Instead, they focus on finding a mate. Larvae are long, white worms that live under the bark for several years.

Crimes: These insects often get a lot of blame for killing trees, but their damage is usually secondary to a larger problem because they are attracted to dead and dying wood. Indoors they can be a nuisance if firewood is brought inside and left for weeks without burning it. They pose no threat to humans, but it doesn’t mean it can’t give you a heart attack when you see one crawling across the floor.

Redeeming Qualities: They assist in the decomposition process.

Sentence: Your best option is to keep your trees healthy, fertilized and watered. A stressed tree is most susceptible to damage form longhorned beetles. Once you see emergence holes in a tree, the damage is done. If the damage is in firewood, it is mainly cosmetic. To prevent beetles from emerging early inside your house, store the wood outside until the day you are ready to burn it.

For more information on dangerous and beneficial bugs, call UI Extension educator Joseph Sagers at 208-745-6685 or email