While boxelder bugs do not cause significant damage to landscape plants, but they may become a nuisance by invading homes in the fall in California. If boxelder bugs become a problem, seal up entry points such as cracks and screen windows and doors, and eliminate hiding places and debris outdoors.
Boxelder bugs are sometimes confused with other bugs such as squash bugs, the bordered plant bug, leaffooted bugs, and others. You can find out more about boxelder bugs in the newly revised Pest Note by E. J. Perry and K. Windbiel-Rojas at http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74114.html.
Author - Associate Director for Urban & Community IPM/ Area Urban IPM Advisor