Insecticides targeting adult mosquitoes (adulticides) are an important tool, as they are the last line of defense against nuisance and virus-carrying mosquitoes.  Adulticides are sprayed by truck and/or airplane in response to high mosquito populations, or areas with known mosquito-transmitted disease (such as West Nile). STPMAD uses only EPA-registered products that have minimal risk to non-target species, and strictly follow legal requirements for calibration and timing of spray events. Adulticides are sprayed primarily after sunset, a period when mosquitoes have been shown to be most active, and when honeybees and other beneficial insects are least likely to be encountered.

Adulticide products used by St. Tammany Parish Mosquito Abatement are listed below:

  • Pyrethroids and organophosphates interfere with the nervous system of adult mosquitoes.
Product SDS Label
Duet Duet SDS Duet Label
Scourge Scourge SDS Scourge Label
DeltaGard DeltaGard SDS DeltaGard Label
Dibrom Dibrom SDS Dibrom Label
Fyfanon Fyfanon SDS Fyfanon Label

At the request of public park and recreational facilities, we can apply a perimeter treatment to control mosquitoes around sports fields. These treatments are applied by ATV along the woodline surrounding the sports fields to target resting adult mosquitoes.

Adulticide products used by St. Tammany Parish Mosquito Abatement at Recreational Facilities are listed below:

  • Pyrethroids interfere with the nervous system of adult mosquitoes.
Product SDS Label
D-Fense D-Fense_SC SDS D-Fense_SC Label

EPA Naled Recommendations

The Environmental Protection Agency (EPA) has issued new recommendations for mosquito control aerial applications of Naled. The recommendations are currently being presented in the draft Human Health Risk Assessment and Ecological Risk Assessment for Naled and are currently under review and pending approval for 2022. The new guidance recommends a lower application rate (0.05 lbs a.i./acre at a 300’ release height) than what is currently recommended by the EPA for Naled aerial applications, as well as new guidance on steps to take following a spray treatment. St. Tammany Parish Mosquito Abatement currently applies Naled at a rate of 0.075 lbs a.i./acre at the higher 300’ release height. We are in the process of recalibrating our aircraft to meet the new standards in preparation of the 2021 mosquito season.

***Note: You can register to receive notification of an aerial spray application by clicking here.

U.S. Environmental Protection Agency Recommendations for Reducing Exposure to Naled

  • Stay indoors with the windows closed during spraying.
  • Do not allow children to play outdoors for four hours following spraying.
  • If you are outdoors when spraying takes place and come in contact with the chemical, rinse your skin and eyes with water.
  • Wash fruits and vegetables from your garden before storing, cooking, or eating. This is a good habit, regardless of whether mosquito spraying has occurred.
  • Cover outside items like furniture and grills before the spraying takes place. Bring pets and items like pet food dishes and children’s toys indoors. Rinse any uncovered items left outside during spraying.
  • If you think you have had a reaction to the spraying of Naled, talk to your doctor or call the regional Poison Control Center at 1-800-222-1222.


The EPA also states, “If applicators choose to apply the product at lower rates (0.05 lb a.i./acre) in combination with smaller droplet sizes, higher release heights, and higher wind speeds, the application would lead to less deposition, less exposure and fewer risks of concern.”