The national park protects one of the most diverse areas of vegetation in the country. The park's lush rainforests include one of the largest upland subtropical rainforest remnants in the world and the most northern Antarctic beech cool temperate rainforests in Australia. The roots of the oldest Antarctic beech trees are over 5,000 years old. Around Mount Widgee numbers of Antarctic beech appear to be increasing. The park protects one of the country's largest remaining forests of hoop pine ("Araucaria cunninghamii") which are found on the drier slopes.