Does the koala eat anything other than eucalyptus?
Koala
Koalas typically inhabit open eucalypt woodlands, and the leaves of these trees make up most of their diet. Because this eucalypt diet has limited nutritional and caloric content, koalas are largely sedentary and sleep up to 20 hours a day. They are asocial animals, and bonding exists only between mothers and dependent offspring. Adult males communicate with loud bellows that intimidate rivals and attract mates. Males mark their presence with secretions from scent glands located on their chests. Being marsupials, koalas give birth to underdeveloped young that crawl into their mothers' pouches, where they stay for the first six to seven months of their lives. These young koalas, known as joeys, are fully weaned around a year old. Koalas have few natural predators and parasites, but are threatened by various pathogens, such as Chlamydiaceae bacteria and the koala retrovirus, as well as by bushfires and droughts.
Eucalyptus punctata
The grey gum regenerates by regrowing from the base and branches after bushfire. Trees live for over a hundred years. The grey-headed flying fox ("Pteropus poliocephalus") eats the flowers, while the leaves form a staple of the diet of the koala ("Phascolarctos cinereus"). Leaves in winter contain less nitrogen than those in summer, which the koalas make up for by eating more in winter months. The brown-headed honeyeater ("Melithreptus brevirostris") and yellow-tufted honeyeater ("Lichenostomus melanops") have been observed eating gum exudate from the stems. 
Fieldwork at several sites around central New South Wales showed that the red wattlebird ("Anthochaera carunculata") and noisy friarbird ("Philemon corniculatus") preferred to forage on the foliage of the grey gum over other trees, with the former appearing to oust the latter if both species were present.