Scribbly gums are spectacular Australian trees with smooth, whitish yellow bark. The bark has a prominent feature which puzzles many people – strange looking ‘scribbles’ resembling some form of mysterious, ancient writing. The zigzag tracks are actually tunnels made by the larvae of a moth called Ogmograptis scribula, and they’re interesting because they reflect the life cycle of the insects. Increases in the tunnel diameter show that the larva is growing, and the end of the track is where it has stopped burrowing and started to pupate. The adult moth is rarely seen, but the markings it leaves behind only enhance the beauty of these lovely trees.