Though Cal Fire has kept completely mum on the investigation of the Lockheed blaze, one has to wonder how the cause of an all-consuming 7,817-acre blaze could ever be determined in the first place. "Most people think that everything is destroyed in a fire, but that's not true," says Division Chief Mark Ramos of the Santa Cruz Fire Department. "The biggest factor for us in a fire this big is, where in the heck do you start looking at these indicators?"

Ramos says there are plenty of telltale signs in nature that can help fire investigators pinpoint the origin. Burn marks on trees and the patterns in fallen weeds and grass, which will fall toward a heat source, help them zero in on the origin before they start investigating possible causes. Much of the investigation is just ruling out possibilities. For example, Ramos says just checking the weather the day it broke out rules out some causes--many days the humidity in our area makes it nearly impossible for a discarded cigarette to set a fire.

If the cause is believed to be human, things get more technical. "We have a sniffer, I call it a mechanical dog. It's a machine that has a sensor. It's going to detect hydrocarbons present in things like gasoline, diesel," says Ramos. The sniffer will also pick up things like carbon build-up that has been backfired from a tail pipe, which was determined to be the culprit of the Trabing fire a year ago. Besides physical evidence, fire investigators rely on good old-fashioned gumshoe detective work like interviewing witnesses and first responders. "You're building theories, you create a hypothesis and you test that hypothesis," he says. "When I do fire investigation I'm not a scientist, but I do the scientific approach."

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