The Leavenworth Mosquito Control (LMC) District will begin larvicide treatments as soon as mosquito larva are present; March 15th (earliest) continuing until October 15th (latest)
The larvicides used include Bacillus thuringiensis subspecies israelensis, Bacillus sphaericus, and methoprene. Spinosad may also be used. In addition, a paraffinic white mineral oil may be used as both a larvicide and a pupicide.
LMC District seeks to reduce mosquitoes through habitat reduction and larviciding. Adulticides were not used from 2007 through 2023. If an adulticide is needed however, we may choose to use malathion, natural pyrethrins, piperonyl butoxide (PBO), permethrin, etofenprox, naled, prallethrin, resmethrin and/or sumithrin. Such spraying could occur in June, July or August anywhere within the LMC District and will be noted on our website: www.leavenworthmosquitocontrol.org
Larvicide “Treatment Sites & Locations” are posted at this website. Additional sites may be added as needed.
More information on these pesticides is available online at http://npic.orst.edu/pest/mosquito/
For additional information, or to be placed on a “No Spray List”, email to: info@LeavenworthMosquitoControl.org, or contact Manager Jennifer Mullins at 509-548-5904 directly. Note: Placement on the “No Spray List” is not a guarantee of general non-treatment.
The Department of Ecology Aquatic Pesticides Permit Manager may be reached at (360) 870-3492 (mobile) or email to shawn.ultican@ecy.wa.gov