Aerial Treatment to Begin for Spring Mosquito Larvae in Saginaw County

The Saginaw County Mosquito Abatement Commission’s annual Spring Aerial Treatment Program
is tentatively scheduled to begin Thursday, April 9th. This multi-day operation targets spring
mosquito larvae developing in seasonally flooded woodlots throughout Saginaw County.
Treatments typically occur in April, when larval development peaks and spring habitat is most
abundant. Weather conditions such as strong winds, low temperatures, or rainfall may delay the
start or extend the treatment period.

This year’s program will treat approximately 50,000 acres of woodland floodwater mosquito
habitat near populated areas. The application uses Bacillus thuringiensis israelensis (Bti), a
naturally occurring soil bacterium applied by aircraft at a low rate of 2.5–3 pounds per acre. Bti
is short-lived and specifically affects mosquito larvae, blackflies, and fungus gnats. Mosquito
larvae must ingest the material for it to be effective.

The Spring Aerial Treatment provides early-season relief from biting mosquitoes and supports
public health by reducing species capable of transmitting West Nile virus and Jamestown
Canyon virus.

Aerial services are provided by Al’s Aerial Spraying (Ovid, MI). Eight yellow aircraft will operate
from the Saginaw County H.W. Browne Airport in Buena Vista Township during the treatment
period.

Following the aerial application, SCMAC staff will begin community-level treatments and
respond to resident service requests. Summer mosquito levels and mosquito-borne disease risk
depend heavily on weather patterns. Wet conditions tend to increase mosquito nuisance, while
hot, dry periods can increase activity of viruses such as West Nile virus.

The Saginaw County Mosquito Abatement Commission remains committed to protecting public
health and delivering valued services to county residents. For daily updates, visit our website,
follow us on social media, or download our mobile notification app. Additional program
information is available at saginawmosquito.com or by calling 989-755-5751, Monday–Friday,
8:00 a.m.–4:30 p.m.