What is in that red fire retardant?  It’s not as bad as it looks…

What the air tankers are dumping is a fire retardant known as slurry, a mixture of mostly water and fertilizer designed to protect trees and other flammable material from flames. The coating clings to vegetation and insulates it from the approaching inferno; the fertilizer helps the damaged areas regrow in the wake of the blaze. The powdery concoction is a key ingredient of a multi-pronged firefighting strategy; after the air drop, bulldozers and ground crews move in to cut a fire break designed to halt the advancing flames.

Slurry is dyed bright red to aid in visibility and help tanker pilots drop a seamless line of retardant. “Basically, they’re trying to box in the fire,” says Janet Upton of the California Department of Forestry and Fire Protection (Cal Fire), which is helping to battle the giant Station fire near Los Angeles. Another advantage of slurry is that unlike water, fertilizer doesn’t evaporate. (It offers still another bonus for farmers, who have requested that unused slurry be dropped onto their fields as aircraft make their way home.) – via Time.com

I wondered this on my drive to work today past thousands of acres scorched by recent fires.  The Forest Service recommends not to let your pets consume it…

Though slurry doesn’t look particularly eco-friendly, aerial firefighting is not environmentally harmful, Upton says — though planes avoid dumps near lakes, streams and other waterways (in especially sensitive areas, tankers drop plain water instead). The Forest Service also advises against allowing pets to swallow the stuff, as with other fertilizers. Still, the retardant poses another, less-publicized hazard, Upton says: to fashion. She’s been on the ground as a rain of colored fertilizer falls from the sky: “I’ve had plenty of pink t-shirts.”via Time.com

(photo via MTPR)