Alas, we can’t eradicate them. With over 3,500 mosquito species worldwide and more than 400 in the U.S., they’re here to stay. But there are ways to prevent them from ruining your next s’mores night around the campfire—and keep yourself mosquito bite-free.

Why Mosquitoes Bite

While it seems like it, we’re not a mosquito’s favorite meal. “Many mosquitoes wouldn’t bite a person—they bite frogs, birds, lizards,” says Dina Fonseca, Ph.D., chair of the department of entomology at Rutgers University. “But we’ve domesticated them to realize that we’re a source of blood.” That’s especially true of some invasive mosquito species like the Asian tiger mosquito, which are the most likely to bite you. “They’re becoming very large populations, because they don’t have any competitors or predators and can exploit the environment.” Mostly, mosquitoes live on sugar from plants, and they actually help pollinate some flowers. “Only female mosquitoes bite—they’re little moms getting blood to be able to make eggs,” Fonseca says. “They use the blood to feed the eggs.”

Preventing Mosquitoes

There are ways to make your yard less enticing to mosquitoes—and fortunately, most of them just require a little work (and no money!) on your part. Remove all standing water. You’ve probably heard this before but, when they say all standing water, they really mean all. “No water, no mosquitoes,” states Fonseca. Unfortunately, even the smallest amount of standing water results in too many mosquitoes. “We’re talking about a yogurt container, saucers under plants, planters that don’t have drainage holes and may fill up with too much water, the accordion extension pipes for gutters,” Fonseca says. “We cleared out one of those and found 500 larvae for Asian tiger mosquitoes.” Be especially careful with covering recycling bins—even a little rainfall can collect in your recycled bottles and cans and provide places for mosquitoes to lay their eggs. “Plastic was the best thing that ever happened to mosquitoes,” Fonseca adds. Get your neighbors on board. Mosquitoes don’t respect property lines, so your neighbor with the swampy-looking planter can breed a whole army of mosquitoes poised to invade the neighborhood. Mention that to your neighbor so they can make their yard (and yours) less attractive to mosquitoes. Call your local mosquito control program. Most U.S. counties have a program dedicated to keeping mosquitoes at bay. If you suspect that mosquitoes are coming from marshes or other wet areas around your neighborhood, the county may be able to help. In many cases, environmental changes cause mosquitoes to breed in a different area than where the mosquito control program has treated. “Climate change can change the distribution and abundance of mosquitoes,” Fonseca says. “For instance, on the coast, sea level rise is flooding areas that didn’t used to flood, so the hotspots for mosquitoes may be changing.” Set a trap. Bug zappers are cool, but the best trap is a DIY one that involves two different-sized buckets and some sticky tape or flypaper. “You add in water, a little grass or yeast to make the environment an enticing place to lay eggs,” Fonseca explains. “Then you put canola oil on the sides of the container and flypaper, so they get stuck.”

Preventing and Treating Bites

Even if you’re super-vigilant, odds are you’ll still attract a few mosquitos, but these tactics can make yourself less attractive:

DEET - Yes, it’s a harsh chemical, but Fonseca says it’s effective at keeping mosquitoes off you.Lemon and Eucalyptus Oils - Fonseca started using this after she developed a reaction to DEET, and finds it very effective.Fans - Running a fan creates a breeze that outmatches a mosquito’s tiny wings, but still leaves you a little exposed. “A mosquito can figure out a way,” Fonseca says. “I got bit on my back—the mosquito used me as a shield from the fan.”

What Doesn’t Work

Some commonly used mosquito deterrents don’t do much to stop mosquitoes—so you might want to reconsider using these:

Citronella Candles - Sorry, those lemony citronella candles don’t hold a candle to other options for preventing mosquito bites.Mosquito Treatment Companies - Fonseca says the jury’s still out as to whether they work, and she has doubts. “We know very little about how effective private companies are,” she admits. “The best way to get rid of adult mosquitoes is to get rid of them as larva with larvicides.” Also, commercial treatments may end up killing beneficial insects along with the mosquitoes. “Then you’re replacing a mosquito problem with a plant-based problem, with aphids and whiteflies increasing.”