Last December, one of my best friends sent out a desperate group text calling for moral support when her freshly decorated Christmas tree suddenly exploded with tiny baby praying mantises (here’s what you need to know about creepy praying mantises). This is a friend who, I must add, really, really hates bugs. Soon the baby mantises were all over her apartment and her Christmas cheer had dissolved into anxiety as she tried to vacuum them all up and dragged the tree to the curb. Not exactly the jolliest way to kick off the holiday season (Attention procrastinators! Here’s a last-minute gift for the nature-lover in your life: The Rodale’s Organic Life 2017 Calendar has 365 days of seasonal recipes, inspiring imagery, and gardening tips!)
In the hopes that no one else has to go through this type of Christmas horror, I got in touch with Nancy Troyano, Ph.D., an entomologist for the family of pest control brands Ehrlich, Western Exterminator, and Presto-X, to find out which insects are the most likely to be hiding in Christmas trees and the safest ways to get rid of them. (Find out which is more eco-friendly: a real Christmas tree vs. an artificial one.)
There are a handful of insects that make their homes in pine trees—the most common include aphids, adelgids, scales, bark beetles, psocids, and mites (from abandoned bird nests)—and some, like praying mantises, lay their eggs on tree branches. The reason you aren’t likely to notice the little buggers right away is that the insects go dormant for winter. “As soon as you bring the tree indoors and warm them up, they spring right back to life,” Troyano explains. Or in the case of praying mantis eggs, they hatch.
The good news? None of these insects will cause an infestation in your home, and they're completely harmless...though a major invasion might take a toll on your sanity. (Steal one of these 7 charming Christmas traditions from around the world.)
Troyano’s best advice for keeping unwanted bugs out of your house is to give your tree a good, old-fashioned shake before you bring it inside to dislodge any unwanted visitors. Some Christmas tree lots have mechanical shakers and do the job for you, but your muscle power will be effective, too. Then check the tree over carefully using a flashlight and remove any egg masses or bird nests that you find. Under no circumstances should you spray your tree with an insecticide. Aside from being harmful to you and your family (especially when applied inexpertly), an aerosol insecticide will make your tree extremely flammable.
Phase two of Operation Insect-Free Tree is to keep the vacuum handy. If you suck up the dead needles under the tree regularly, you should also catch any rogue insects. For larger issues that slip past you, as in my friend’s case, the vacuum is still your best line of defense for getting rid of pests quickly. “Most stowaways die pretty quickly as they are ‘outdoor’ pests, and the indoor environment combined with lack of food will kill them,” Troyano explains. That means you don’t need to worry about pests multiplying or causing a lasting infestation that would require you to call an exterminator. Troyano adds that insects tend to “jump ship” when their host plant dies, so a tree that’s been sitting on a lot for a week is less likely to be harboring pests than one you just cut yourself at the local Christmas tree farm. Trees shipped from warmer climates may have higher pest activity, as well.
If you’ve never had a pest problem with your tree in the past, these steps may seem unnecessary. But you never know when the baby mantises will strike, so make Christmas tree shaking a part of your annual holiday traditions. (Take your celebration up a notch with these 8 Danish Christmas traditions you should definitely steal.)