When you buy a Christmas tree, you probably don’t spend a lot of time thinking about the bugs that might have called it home at one point. But experts say little creepy-crawlies called aphids like to hang out on Christmas trees—and if you have a tree in your home, they might be on yours right now.
Aphids are soft-bodied insects about the size of an ant that use their piercing, sucking mouthparts to eat the sap that’s on your tree. Aphids come in many colors—green, black, brown, or red—and some also have wings. And, unfortunately, they can end up in your house.
Aphids hibernate, but if they set up camp on a Christmas tree that’s outside and then taken into a warm house or apartment, they can wake up, Roberto M. Pereira, Ph.D., a research scientist and entomologist (a person who studies insects) with the University of Florida, tells SELF. “They think it’s springtime and start moving around and showing up,” he says.
Aphids are also pretty small—about three millimeters in length—so they’re not easy to spot when you’re out Christmas tree-hunting. As a result, you may end up buying a tree that’s covered in them and not realize it. “They’re not very apparent to people who aren’t used to them, but once they start walking around you can see them,” Pereira says. “They form huge colonies on plants.”
Obviously, that can be a little freaky, especially since aphids look a lot like ticks. However, Pereira points out a few differences between aphids and ticks: Ticks have eight legs, while aphids have six, and aphids have a tear drop-shaped body, while ticks are more flat. They also have thin skin (ticks have thick skin).
Luckily, unlike ticks, aphids don’t bother people. “They have no desire to come into your house and impact you,” Ron Harrison, Ph.D., Orkin entomologist, tells SELF. “They don’t bite you—they’re just a nuisance.” However, if they crawl off your tree and get squished on your furniture, rug, or curtains, they’ll leave a stain, Pereira says.
If you’re not exactly thrilled at the idea of having an aphid infestation in your house (understandable) but want a Christmas tree, there are a few things you can do. Harrison recommends asking whether your tree was treated for aphids in advance (some tree-sellers do this), and requesting that your tree is shaken with a mechanical tree-shaker before you take it home, which will help remove the flying type of aphids.
If you have a garage, Pereira recommends leaving your tree in there for a day after you bring your tree home, and then inspecting it before bringing it inside. A garage should be warm enough to wake up any hibernating aphids, he says. Aphids are usually more of an issue right after you bring a tree home since it hasn’t dried out much yet, and you may be more prone to having an aphid-infested tree if you cut it on the spot versus buying one at a tree yard, also due to dryness, Harrison says.
Luckily, if you spot aphids, there’s an easy, nontoxic way to get rid of them. Pereira suggests mixing two spoonfuls of liquid soap, one spoonful of any kind of cooking oil (vegetable oil, olive oil, etc.), and four ounces of water in a spray bottle, and spritzing the bugs with it. “You can just ‘hose’ down the tree—it won’t bother the plant,” Pereira says. (If you want to be extra-cautious, Harrison says you can spray your tree with this soapy mix before you decorate it.) If you see aphids crawling around on your tree or around your house, White says that to get rid of them but avoid stains, you can simply vacuum them up.
But if your tree is already decorated and you don’t want to get it wet or turn a vacuum loose near your ornaments, no need to worry. While aphids can get off your tree and crawl around your house, Pereria points out that they really prefer to just stay put, and either way, they'll die eventually without posing any threat to your health.