A group representing crop-dusting pilots in Australia is calling for a national effort to mark power lines so pilots can safely avoid them, ABC-Australia reported on Tuesday. The appeal from the Aerial Agricultural Association of Australia follows two helicopter crashes within three days. Both helicopters were spraying for locusts and hit power lines. Peter Mackay, president of the pilots' group, told ABC that aerial spraying is risky, and precautions are necessary. "We'd like to see these power wires marked more openly," he said. "They are very hard to pick up from the air and in low conditions perhaps when you've got sun in your eyes, or trees in the background." The pilot in Monday's crash, in New South Wales, escaped with minor lacerations when his Bell 47 crashed and burned. On Saturday, a helicopter with a pilot and three others on board crashed in the same region, but no one was hurt.