The Junkers took off from Tucum n at 17:40 for a locust control spraying flight in the mountains near San Pedro de Colalao. The aircraft carried 2400 liters of gasoline, 180 liters of oil and 1000 liters of liquid locust spray. After making two spraying runs the pilot turned towards the ravine. The pilot than saw a swarm of locusts in flight near the crop. At low altitude, while making a left turn to follow the course of the ravine when the port wing struck a tree. The aircraft crashed into the woods and caught fire. PROBABLE CAUSE: “Lack of technical experience on the part of the pilot in carrying out a spraying flight over mountainous terrain, resulting in his failure to allow adequate terrain clearance. Contributing factors were the type of operation, the nature of the area flown over and the type of aircraft used.”