In less than a minute, a burning Christmas tree can produce room temperatures of 1,000 degrees Fahrenheit, said West Valley Fire Marshal John Blundell.

"At that temperature, everything in the room will ignite. Essentially, everything in the room above the 3-foot level will be burning," Blundell said. "It makes escape much more difficult and the potential of personal injury a lot greater."At a demonstration outside Fire Station No. 73 of how quickly and hot a tree can burn, Blundell urged the use of fire retardant.

A road flare was unable to light a tree treated with the fire retardant, but an untreated tree readily caught fire and burned fiercely.

The treated tree finally caught fire after being placed between two burning untreated trees but it burned only fitfully. The flames stopped and started, and finally died altogether after the other two trees burned themselves out.

Fire retardant is required by law on any tree placed inside a public building or school.