Director of the North Elba Black Fly Control Program John Reilly demonstrates how technicians measure the width of a stream, in this case the Chubb River, to calculate how much Bti to use.

LAKE PLACID — A team of expertly trained killers are roaming the woods and fields around Lake Placid, making sure you and your family won’t get eaten this summer — by the black fly.

Infamous throughout the Adirondacks, the black fly is the notorious pest that everyone loves to hate. Since its inception 15 years ago the North Elba Black Fly Control Program has been using Bti (Bacillus thuringiensis israelensis) as its weapon against the annoying critters.

From April 1 through mid-July, black fly technicians cover a 90-square-mile area centered around the village of Lake Placid from MacKenzie Pond in the west to Mount Van Hoevenberg in the east, and from the end of Averyville Road in the south to Whiteface Landing in the north. That includes about 250 miles of waterways.

The town of North Elba is one of the most extensive of the roughly 30 Adirondack townships that have a black fly control program.

Black flies are considered