MISSOULA, Mont. (AP) — U.S. Forest Service workers have exchanged axes and saws for sticks of high explosives in southwestern Montana to bring down beetle-killed pine trees that pose unique dangers.

Crew member Gordon Ash says workers brought down some 500 trees last week in the Pioneer Mountains by blowing up the trunks. He says beetle-killed trees often rot from the inside out, making them prone to shattering and falling in unpredictable ways.

Charlie Showers of the Missoula Technology and Development Center says another problem is the Forest Service doesn't have many sawyers because the days of doing that activity are long gone.

Showers tells the Missoulian that crews are learning the most efficient way to bring down beetle-killed trees with explosives.