Weather-permitting, the Delaware Department of Natural Resources and Environmental Control Mosquito Control Section within the Division of Fish & Wildlife will begin its annual spring woodland pool spraying campaign March 23 downstate, and possibly March 24 upstate, treating wooded wetlands near select populated areas in New Castle, Kent and Sussex counties.

In most years, about 10,000 forested acres that produce large numbers of early season mosquitoes are strategically sprayed, using larvicides applied by helicopter and fixed-wing aircraft.

Over the next few weeks, Mosquito Control will apply a bacterially-produced insecticide, Bti.

Aerial spraying of woodland pools must be completed before the forest canopy fills in, usually around mid-April, because foliage prevents the insecticide from reaching woodland pools and other wet spots on the forest floor containing mosquito larvae. The spring campaign marks the beginning of Delaware’s annual mosquito season, which in most years continues until mid-October or early November, depending upon when the first frost occurs.

Residents are encouraged to reduce mosquito-producing habitat by cleaning clogged rain gutters and downspout extenders, keeping fresh water in birdbaths, draining abandoned swimming pools and preventing or emptying standing water from containers such as scrap tires, cans, buckets, flower pot liners, unused water cisterns, children’s toys, upright wheelbarrows, uncovered trash cans, depressions in tarps covering boats or other objects stored outside.

As in the past, public notice of when and where spraying for adult mosquitoes will occur this year will be available via daily radio announcements and by calling 800-338-8181. Interested parties may also subscribe to receive email, text or phone message notices of mosquito control spraying in their area by signing up on the Spray Zone Notification System at

To request localized mosquito control, call Mosquito Control’s field offices:

— Glasgow Office, 836-2555, serving New Castle County and the northern half of Kent County, including Dover.

— Milford Office, 422-1512, serving the southern half of Kent County south of Dover and all of Sussex County.

For information, call at 739-9917.