Yes, Bifen IT would work to treat flies. It dries clear and is odorless. You can apply the mixed solution to lawns, trees, shrubs, and indoors. It has a long lasting residual. You will need to retreat during the fly season once every 30 days.
We would recommend using Hi Yield Indoor/Outdoor Permethrin 10% Insecticide. It is safe for use on edibles and is labeled for mosquitoes. The mixing ratio is 1-3 oz. per 4 gallons of water. This will treat approximately 4000 square feet. This can also be used in your lawn for mosquitoes as well.
Bifen IT is available for licensed professionals to apply in New York State. We are not able to ship to homeowners but whether you could legally use it would be something you need to ask of the local department that handles pesticide regulations.
Vector Ban Plus does not leave any kind of residual so will only kill the mosquitoes that are out in the open at the time you are applying to product.
You are on the right track with using a residual product like Bifen IT or Demon Max, it is actually our most popular product for mosquitoes. The key is to apply it to the underside of leaves of trees and bushes as that is where the adults lay during the day. Bifen would be the more recommended as it known to be super gentle on plants but you can rotate them as well.
Bifen IT is not labeled for use in horse pastures or other animal grazing areas. You can use Essentria All Purpose for fire ant mound drenching. In Spring and Fall, you can use Extinguish Fire Ant Bait as a broadcast and mound baiting application. We have more tips on these applications in our Fire Ant Treatment Guide here.
Bifen IT can be applied monthly (30 days) outside the home and every 3 months (90 days) inside around the cracks and crevices.
If you are using Bifen IT to treat an active flea infestation, you will need to re-treat 14 days after your initial application. It is strongly recommended to also use an insect growth regulator (IGR) such as Archer IGR in addition to the Bifen IT in order to stop the fleas from reproducing. Please take a moment to read over our Flea Control Guide for more information on how to implement a successful eradication program.