Mosquito control

Why not spray the yard?

Sitting out on the porch, deck or lawn--it's one of the best parts of spring and summer. Those pesky mosquitoes can really interfere with the enjoyment. There are many companies advertising that they will spray your yard to get rid of mosquitos. But the sprays they use kill ALL insects in your yard, including the bees, moths and butterflies you might be trying to attract with pollinator-friendly plantings. Scroll on down for more information, including ways to reduce the mosquite problem without killing all the beneficial insects. 

Mosquito sprays kill bees

They also kill butterfiles, moths and other beneficial insects. The sprays used by mosquito control companies are generally pyrethrins or pyrethroids. People promoting home spraying like to point out that pyrethrins are naturally derived compounds, but they still kill all kinds of insects. There are different types; one that we have seeen in our area is called bifenthrin. It may provide what is known as a barrier treatment; the spray sticks to leaf surfaces and kills mosquitoes and other insects that land on the plants for up to three weeks. However it doesn't keep mosquitoes from continuing to fly into your yard. This is one of the reasons that the spray companies encourage groups of neighbors to sign up by offering discounts. This practice harms other insects all summer long throughout the neighborhood. There are subsequent ill effects on birds, fish, reptiles and other animals that depend on insects for food. 

So how can we control mosquitoes?

First, consider reducing the impact of mosquitoes on your activities. They are slow flyers--experiment with fan placement on your porch to find the best angles. Insect repellents work, especially those with DEET. Cover up by wearing long-sleeved shirts and pants. Clothing treated with permethrin is very effective, doesn't smell at all, and according to the EPA it is considered safe for most people.  Permethrin also protects against ticks--many FOCHT stewards use clothing treated in this way. You can buy clothes already treated, buy sprays to treat your clothes, or send your clothes away to be professionally treated. 

You can plan ahead to prevent mosquitoes from hatching by making sure there is no standing water on your property. Check downspouts and outdoor furniture and toys to be sure they aren't holding pools of water. If you keep bowls of water for the dog or a birdbath, replace the water weekly, or get a bubbler. Have the kids do a puddle check on summer weekend mornings while you enjoy your early coffee on the patio! If you need to leave a puddle for some reason, consider using dunks or other products that contain Bti. This is a bacterium that specifically kills the larval stages of mosquitoes and blackflies. It does not harm bees or butterflies. 

Make dunk buckets to trap mosquitoes

You can lure female mosquitoes into laying their eggs in buckets of water that contain Bti. The eggs will hatch but the larvae won't make it to adulthood. While one dunk bucket probably won't have much effect, there is some evidence that strategically placing buckets around a neighborhood can reduce the adult mosquito population, and a few communities have experimented with this. You can buy commercially produced buckets or make your own--there are numerous internet sources explaining how to make these mosquito larva traps. This one is pretty straightforward. People have used everything from 5 gallon buckets to some of the fast food containers they still have around from Covid days. 

Want some help to get started?

Well, come out to the Barmouth Trailhead on the Cynwyd Trail on Sunday, May 5 from 3-5pm to learn more! If you bring your bucket or other container, we'll supply you with a mesh cover to keep out non-target organisms and your first round of Bt, for free!! Bring your neighbors and get started on controlling mosquitoes in a way that you can feel good about. 

I want to know more...

Great, the more you know the better equipped you will be to control mosquitoes in your yard--every place is different. Here are some places to start:

A summary by Beth Yount, from Penn State, details the problems that chemical mosquito control poses, especially along streams. Beth is a trail neighbor, and her article also links to other great resources.

This blog entry from local nature photographer Colin Purrington is full of practical information that you can use in reducing mosquito presence in your space. 

This publication was used to educate neighbors in University Park MD, one of the communities trying a grass roots approach to control mosquitos. It includes great images of places where mosquitos can breed and also mentions some of the commercial traps available. 

Want to help get the word out?

If you would like a sign like the one you see here, send an email to and we'll figure out how to get you one for your yard.