AFTER COMPLETION OF AN AERIAL APPLICATION OPERATION, THE PILOT MADE A CLIMBING TURN TO RETURN TO THE STAGING AREA. DURING THE CLIMB, THE ENGINE LOST POWER AND AN IMMEDIATE EMERGENCY LANDING WAS INITIATED. HOWEVER, DUE TO LOW ALTITUDE, THE PILOT WAS UNABLE TO GLIDE THE AIRCRAFT TO A SUITABLE LANDING SITE. THE AIRCRAFT COLLIDED WITH TREES AND THEN THE TERRAIN. A SUBSEQUENT INVESTIGATION REVEALED THAT ONLY UNUSABLE FUEL WAS REMAINING IN THE AIRCRAFT.