Eliminate winter hideaways for boxelder bugs
In May 2021, I had my flower beds remulched with new mulch. The landscaper removed my old mulch first. That summer I had a great many BE bugs in my backyard flower beds. My neighbor has a silver maple tree and when it dropped all its seed pods the BE bugs just devoured them. I did not do new mulch this year, but still had many BE bugs and they ate the roots of all my annuals. Is it possible that the BE bugs came in with the new mulch? Is there anything I can do over the winter to rid the beds of them? Specialists I contacted could not guarantee to get rid of them, but the cost was well over $1,000. Any suggestions?
— Kathy Kuchinos
First, for those unfamiliar
with this pest, boxelder bugs (Boise trivia) are about a half-inch long, They have narrow black bodies, and red lines on the edges of their torsos and on the edges of their wings. They fly well and often.
Boxelder bugs love (what else?) boxelder trees and, as Kathy notes, silver maple. Any areas near either of these trees will see an increased population of these pests. Provide them with a wintering over spot and your property becomes a haven for boxelder bugs.
Another favorite winter haven is your home. Like ladybugs and stink bugs, these pests will invade your home, entering through any small gap. While they love the vacation indoors, they breed outside.
Are they dangerous or harmful? Boxelder bugs are considered a nascence. They eat the seed pods, leaves and flowers of their target plants. Usually, they do little permanent damage and are not known to carry any particular plant disease. Boxelder bugs do not sting or bite, they have no poison but seemingly taste bad so your pets are unlikely to eat more than one.
However, they are annoying. Squashing a boxelder bug can cause a dark stain on whatever surface they were killed on.
Indoors, you can check and repair caulk around windows and doors, and add a sweep to eliminate the drafty gap below the exterior doors. You can vacuum them up but do remember to discard the used bag. Natural-based pyrethrum sprays can be applied to the interior or exterior of the house. If you enjoy such things, the pests can be killed by directly spraying them with a detergent/water mixture (½c dish detergent to a gallon of water).
Outside, the best and obvious solution is to eliminate the boxelder and silver maple trees. However, as much as we’d like to, we cannot make our neighbors get rid of plants that annoy us.
Eliminate winter hideaways, but since that includes mulch, it is impractical.
Other natural options include encouraging birds and spiders, both prey on boxelder bugs. This however will only decrease the population not remove it,
I don’t know what treatment the professionals are offering, but it may include a chemical, nonspecific insect killer. As the name implies, these products will kill much more than the boxelder bugs. Removing and replacing the mulch will only provide a fresh spot for the bugs to live. A soil drench, as noted above, will kill a lot more than the boxelder bugs.
I could find no reference to boxelder bugs eating plant roots since they generally just hibernate there but stranger things have happened and the garden is always full of surprises.
I don’t have a good solution for Kathy. If anyone has suggestions that have worked for them and don’t include cutting down the neighbors’ trees, please let me know.
A few quick reminders
Poinsettias, calla lilies, and amaryllis are tropical plants. While they are great decorative plants, be sure to ...
Cover them when transporting them. Buy them last and deliver them first. Do not leave tender plants in a cold car.
Place these tropicals in an area that does not have drafts, particularly cold drafts. So avoid exterior doorways, fireplaces, air ducts, radiators, and any other sources of hot or cold air.
Check the plants frequently. Generally, there is much less humidity in the house air once the heat is turned on. Expect to water more frequently and consider a gravel-filled tray with water under the plants to increase the humidity.
When you water, be sure to remove any water-tight wrap to allow the plants to drain into a saucer. Dump any excess water. While humidity is good, wet soil will promote rotting.