Eucalyptus globulus

The Tasmanian Blue Gum, Southern Blue Gum or Blue Gum Eucalyptus (Eucalyptus globulus), is an evergreen tree, one of the most widely cultivated trees native to Australia. They typically grow from 30 to 55 m (98 to 180 ft) tall. The tallest currently known specimen in Tasmania is 90.7 m tall. The natural distribution of the species includes Tasmania and southern Victoria. There are also isolated occurrences on King Island and Flinders Island in Bass Strait and on the summit of the You Yangs.

The bark shreds often, peeling in large strips. The broad juvenile leaves are borne in opposite pairs on square stems. They are about 6 to 15 cm long and covered with a blue-grey, waxy bloom, which is the origin of the common name "blue gum". The mature leaves are narrow, sickle-shaped and dark shining green. They are arranged alternately on rounded stems and range from 15 to 35 cm in length. The buds are top-shaped, ribbed and warty and have a flattened operculum (cap on the flower bud) bearing a central knob. The cream-colored flowers are borne singly in the leaf axils and produce copious nectar that yields a strongly flavored honey. The fruits are woody and range from 1.5 to 2.5 cm in diameter. Numerous small seeds are shed through valves which open on the top of the fruit. It produces roots throughout the soil profile, rooting several feet deep in some soils. They do not form taproots.

The Tasmanian Blue Gum was proclaimed as the floral emblem of Tasmania on 27 November 1962. The species name is from the Latin globulus, a little button, referring to the shape of the operculum.

Blue gum is the most common plantation hardwood in Australia. It comprises 65% of all plantation hardwood in Australia with approximately 4,500 km² planted. Most of these plantations are owned by international paper producers. The tree is widely cultivated elsewhere in the world for its timber, and sometimes for extraction of eucalyptus oil from its leaves. It was introduced to California in the mid 1800s and is prominent in many parks in San Francisco and throughout the state.