With recent rain, cooler temperatures, and shorter days, fire management personnel on the Mt. Hood National Forest anticipate the start of fall pile burning season to begin as early as this week and continue for the next several weeks.  Piles are from hazardous fuels reduction projects, timber sales, and timber stand improvement projects.  Slash piles are created when timber stands are thinned, as well as when surface fuels are reduced from the forest floor.  The slash is placed in piles and left to cure before burning.  Crews ignite piles in the morning and early afternoon to allow fuels to burn down prior to evening.  Burn units are monitored by firefighters until they are declared out.  Smoke may be visible in the vicinity during ignition operations and for a short time.