by Cynthia Kerson
They love Manitoba maple trees, also called California boxelder (Acer negundo) locally, hence the name of the bug. Not knowing, I searched what a boxelder tree looks like. UCIPM didn't have a Pest Note or a description of the bugs or the trees, so I explored an outside the website. The trees have small red (male) or yellowish (female) flowers that blossom March-May and remind me of the polliwogs that I grew up with on the East Coast. Their serrated leaves can be white and green or all green. Their multiple trunks are smooth and greyish in color, and they happily mature to about 25'-50' in acidic, low nutritive soils. For this reason, they're common in cityscapes. Having been unaware of the tree, I explored my property and found a couple. Most of what I read advised that the tree borders on ugly as it ages since the flowers are not attractive and droop to look like “dirty socks.” I agree and am not impressed. The ones on my property are outside the fence where “the wild things are.”
The boxelder bugs are about ½” long and red with black markings on their hard backs. They are true bugs with the tell tale "X" on backs of adults insects where their wings fold. When you squish them, they bleed—gross. I am swatting them with a fly swatter whenever I can because I read that they are quite prolific. They will come into the home—good grief! I learned that spraying them with either water and dish soap or a mixture of vinegar, water, and dish soap (I use 45% vinegar), which I keep on hand to spray clover weeds, is a good solution to get rid of them. When I spray the mixture, they drop off right away. I've noticed fewer and fewer of them over the past week, which may be due to my determined effort, the rain and cooler nights, or both. (As an aside: I spray clover, rather than pick it, because if you rustle the plant, it will drop seeds – you can hear them drop if you are close enough). Another remedy for the boxelder bug is to vacuum them, which I have also been doing. Once I have a bunch sucked up, I smother them by wrapping plastic wrap with elastic band on the end of the vacuum hose to be sure they don't climb out and into my garage. At least, I assume they're being smothered. Who knows, I could open the canister and find a boxelder dance party going on! I would check for the sake of this post, but I'm too nervous the latter would be true.
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Photo credits: Cynthia Kerson