Eucalyptus haemastoma: is known as Scribbly Gum. This is one of a number of smooth-barked Eucalypts that have mysterious marks on the trunk. The larvae of a small grey moth burrowing in the bark cause these marks. Scribbly Gum is a small to medium tree. It has an attractive, crooked trunk; glossy leaves and white flowers that appear sporadically throughout the year. The flowers are rich in nectar and are useful for honey production. Koalas will eat the foliage.
Eucalyptus haemastoma is restricted to the Central Coast and Tablelands of NSW. It is a prominent tree in bushland around Sydney. The species could be grown as a specimen tree that would develop into an eye-catching addition to your domestic environment. It would be interesting to observe if the scribbles develop on plants grown out of their natural range.
Propagate from seed.
Eucalyptus rossii is another species that insects use as a writing pad. This is a native of the Slopes and Tablelands of NSW. Eucalyptus rossii is prominent in the Warrumbungle National Park.