mosquito gnats


Greetings, I hope you can help.

We live in Maryland near DC on a half acre.  We have a huge mosquito and gnat problem, I think exacerbated by the bushes and vegetation that borders our entire yard; although the gnats seem thickest just in the yard, not in the bushes areas.  We have had Orkin spray for mosquitoes all summer for several summers and that does seem to help a lot with the Mosquitoes but does nothing for the gnats.  It is only April and the gnats are so thick that the children refuse to play outside for any length of time.  I am at my wits end.  I have read your whole article about gnats and just wonder if money was no object (not true, but I really want to solve this problem) — what would you recommend I do?

I guess I am leaning toward the backpack fogger and using the three chemicals you suggest (Pyrethin, Permethrin & Nylar).  Is this what you would most recommend?  I’ve never used a fogger — is there a danger to my health to use one?  Should I wear a mask?  And do you explain how to mix all the chemicals?

If there is another approach you suggest, please let me know.

Thank you so much,


First, the BACK PACK MISTER is the way to go. I personally use it for all my spraying (insect wise) and it’s both easy to use and very effective. The end spray is like a heavy mist so it’s kind of like spraying with a small pump sprayer. However, so much product comes out and goes so far I’m able to reach out some 25-30 feet no problem. And it’s a nice wide swath that comes out so it’s like a “shotgun” covering a lot of area. This enables the user to treat huge areas with little effort so for me, it’s well worth the investment. And the only safety equipment that’s really needed is EYE GOGGLES, headgear for the sound of the motor and some SAFETY GLOVES. You shouldn’t really need a mask as the end product really isn’t a fog; it’s a heavy mist. If you locate yourself upwind, the spray will always be moving away from you so there is no risk of getting any on you. If you get a Back Pack Mister, I suggest using it with just water in the tank the first time out to “test” how it works. What you’ll find is that with a little practice you’ll no doubt be able to situate yourself in such a way that there should be no chemical coming back to you during the treatment. This means the safety equipment isn’t really needed but it should be worn “just in case”. For me, the ear protection is key as the sound is much like a “blower” which is loud enough to be bothersome.

Second, since I reside in a heavily vegetated region along the Chattahoochee river, I too have a big problem with both mosquitoes and gnats. And the rain we’ve had the past year is only adding to the problem. During the drought we had the past few years I found I only had to treat once a month. But with all the rain we’re now getting, this has all changed.  Now that it’s wet again (or if I’m irrigating all the time) I find a treatment is needed every 10 days at the start of the season and by June maybe only twice a month will keep me pest free. So I say plan on applying product 3 times a month to start; 2 times a month if you’re able to go that long without major problems. Some people need to treat weekly which would be 4 times a month but that would the most extreme situation and not that common.

As for the best products to use; no doubt what you listed would be great. But if you read through our MOSQUITO CONTROL ARTICLE, you’ll see us recommending just BIFEN and NYLAR. Bifen will effectively replace the Permethrin and Exciter and prove to be more cost effective. We started recommending this mixture last year and found it works quite well. Odorless and long lasting, it’s a strong choice and recent price reductions on this product makes the Bifen a great option.

Now do you even need to use the Nylar? Here’s a good way to judge. In my yard, I have so many breeding grounds on 3 sides of my property there is no way my using it would garner any benefit. So for my tank mix, I’m only using 1 oz of Bifen per gallon of water. I’m not using the Nylar and if you feel you too would have breeding going on directly alongside your property in an area you can’t treat, skipping the Nylar would make sense. But if you think the pests are reproducing on your property, Nylar would no doubt really help because you’ll be able to treat their nest sites and in the end, it will help cut down on the frequency of treatments needed per month. For me, the amount of times I treat per month is acceptable and since I didn’t get much benefit if any when I tried using Nylar, I’ve decided to not include it anymore. Clearly each property is different and this is something you’ll need to decide yourself.

As for how much to product to use? Well, I treat about 1 acre and pretty much all four sides of my home up to the roof line of my very tall house and I use just 2 gallons of finished product per treatment. Mixing is quite easy. I fill the tank with 2 gallons of water and add 2 oz of Bifen and that’s it. No shaking as the movement of the sprayer on my back is all the agitation needed to keep it stirred up. And my lot is heavily vegetated so I’m spraying more than most people but I’m also spraying my entire house too. Also, the Bifen could be diluted down much more as you can see on it’s label but I have so many pests I use it at the higher rate. And again, the price is so low right now it’s a great deal. Over 6 months I’ll go through 1 quart of the product and as you’ll see, this isn’t much cost wise so that doesn’t factor in.

Lastly, there is no “danger” when used according to how we’ve explained. Just be sure to keep the pets and kids out of the yard till the treatment dries and you’ll be fine. I like doing my applications around 8-9 in the morning when the yard is moist from the night before. If I know the sun is coming out it will be dry by 10 AM and my dog and kids can go back out with no concerns. Again, it’s odorless and you won’t even know it’s been applied with the only clue anything is different is noticing there are no bugs around following the treatment 🙂

Here are direct links to the products and information posted above:

Back Pack Mister:

Eye Goggles:

Safety Gloves:

Mosquito Control:



Hope this helps!