Issue 2, May 19, 2023

New Requirement for Residential Barrier Mosquito Treatments in Illinois

Barrier mosquito treatment to evergreen foliage. Travis Cleveland. University of Illinois.

A new Illinois law, effective January 1, 2023, aims to protect Illinois residents and pollinators from pesticide residues related to residential mosquito control treatments. Barrier treatments target and control nuisance adult mosquitos by leaving a residual insecticide coating on surfaces where mosquitos rest. Illinois Public Act 102-0916 amended the Illinois Pesticide Act to include additional restrictions and requirements for residential barrier mosquitocide applications.

Required Training

Commercial applicators and operators are now required to complete an Illinois Department of Agriculture approved barrier mosquitocide training program. The University of Illinois Pesticide Safety Education Program recently updated their mosquito applicator training course to include additional topics required by the new law. You can purchase access to the University of Illinois’ course via the Pesticide Safety Education Program’s website: Alternatively, you can participate in an in-person training clinic. Register at the same website. Only two clinics will be offered this spring, so don’t delay. This mandated training must be completed every three years.

Lawn Markers

Commercial applicators and operators must place a lawn marker at a usual point of entry for residential properties treated with barrier mosquitocides. The owner or resident can remove the marker the day following application. The lawn markers are similar to those required for lawn care applications. They must be a 4 inch by 5 inch, vertical or horizontal white sign with letters a minimum of 3/8 inch in a contrasting color. The marker must include one of the following statements:

Information Provided to Clients and Neighbors

Clients can request to receive a copy of the pesticide label and safety data sheet for the barrier mosquitocide applied to their property. Additionally, any neighbor whose property abuts or is adjacent to a client’s property may request to receive prior notification of a barrier mosquitocide application. The client’s neighbor must contact the applicator for hire and provide their name, address, and telephone number. The applicator for hire must notify the neighbor in writing, in person, by telephone, or electronic message of the date and approximate time of application.

Other Prohibitions

The new law also makes it illegal:

  • for companies to apply barrier mosquitocide application between October 16 and April 14.
  • to apply a barrier mosquitocide when wind speeds are greater than or equal to 10 miles per hour
  • to install or use any residential automatic pesticide misting system that automatically sprays any pesticide solution at timed intervals to control mosquitos.

The new law exempts applications that use minimum risk pesticide products that do not require registration under the Federal Insecticide, Fungicide, and Rodenticide Act, as well as any barrier mosquitocide treatment made for public health purposes by or on behalf of a mosquito abatement district, public health department, township, municipality, or other unit of local government.

The Illinois Department of Agriculture mailed licensed mosquito applicators information regarding this new law. Please view their website for additional information regarding this law:

Travis Cleveland

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