Dear Action Line,
Do boxelder bugs have any redeeming purpose? They are all over inside my brick house, proudly appearing across the window screens and on the ceiling. Dropping down onto the floor and humans. Now I’m seeing little ones, so I’m guessing they are procreating? But seriously, are there any reasons for their existence? Indicator species? A food source for better creatures? I hate them!
Bugged out on the Grid
Dear Bugged Out,
It’s always a good idea to respect your elders, and boxelders are no exception. They are so-called for their primary host, the boxelder tree (in the maple family), where they feed on seeds and new leaves. They also thrive on ashes, fruit trees and members of the maple family. The name for the boxelder tree itself comes from the tree’s soft wood used historically for box pulp, combined with its compound leaves resembling elder trees (which produce elberberries).
The “bug” designation refers to its classification as a “true bug” (order Hemiptera), versus lots of other things we call bugs like beetles and flies. So don’t call a Volkswagen Beetle a bug, because it’s not. Neither is Paul nor Ringo.
But yeah, they live up to their “bug” moniker when they are in your house, where they like to swarm on the south side as winter turns to spring (or in our case this year, as autumn turns to spring), to stay warm. While they can leave stains on fabric and wood, at least they are not poisonous.
You apparently live on the “grid” so are probably in an old house, into which invading armies of boxelders can swarm through cracks. But there are steps you can take. Seal up cracks in the foundation and house with caulk, giving special attention to around electrical outlets, switch boxes, heating ducts and return air vents. And if you have boxelder or other host trees that maybe aren’t important to you, consider replacing them with trees that the boxelders don’t use, like evergreens or nonfruiting deciduous trees not in the maple family, like oaks – consult a local nursery.
And as you indicate, like every creature here on God’s green earth they have a role in our ecosystem, both as food for birds and other predators (although they have defenses, see below), and as nutrient cyclers in creating soil. So if you are thinking about killing them, take care not to use poisons, but you can vacuum them up or spray them with soapy water to kill them.
Email questions and suggestions to actionline@durangoherald.com or mail them to Action Line, The Durango Herald, 1275 Main Ave., Durango, CO 81301. Today’s Fun Fact: Boxelder bugs release chemicals that smell and taste bad to deter predators, a strategy similar to that of monarch butterflies and long-horned milkweed beetles. Their vivid red or orange markings serve as a warning sign, allowing them to gather in plain sight without fear of many natural predators, letting them congregate nonchalantly in large numbers.
