Supervisors approved a plan Tuesday designed to stop the woodland pests that can cause serious damage to Fairfax's natural resources.
The 2013 Forest Pest Management Suppression Program attacks gypsy moths, fall cankerworms and other insects known to harm county green space.
The program involves both ground treatment and aerial treatment, which will be carried out by helicopter. Cankerworm treatment will take place specifically in the Mount Vernon and Lee Districts.
The pest control initiatives will kick off around April 2013.
Cankerworms, which are typically called inchworms in the caterpillar stage, feed on leaves, and severe infestations of them can defoliate trees so severely that they die. The worms can have a green or grey appearance. The female moth species is wingless.
They feed on a variety of trees but prefer maples, hickories and oaks, according to the county.
Ground pesticide treatment will help kill both cankerworms and any gypsy moths, costing the county $26,000 for 200 treated acres at $130 an acre.
Aerial attacks will cost about $200,000 for treatment of 2,000 acres at $100 an acre.
Residents in areas scheduled to be sprayed will be notified via mail and will also have opportunities to attend public information meetings at a later date.
Spraying of larger areas will occur from a helicopter, and other, smaller areas will be sprayed by ground. The county will use the pesticides Spinosad, Bacillus thuringiensis/israelensis and Bacillus sphaericus, environmentally friendly chemicals that are accepted as safe for humans.
Gypsy moths in particular have been a major problem in the past, Chairman Sharon Bulova said Tuesday.
“There was a time when the gypsy moth infestation was the absolute biggest thing in the county,” Bulova said. “This is important work that we do to make sure that we are protecting our wooded areas.”
Fortunately, initial survey data shows that gypsy moth populations will remain low in 2013, county staff said.
Residents will have the ability to opt out of the spraying if they so choose. Details for that process will be made available during the public outreach period.
The Board also approved Tuesday measures to prevent West Nile Virus in the county. Read more about that initiative by following the link.