Gum trees dominate the Australian Landscape like no other plant. They range in size from low spreading shrubs to tall forest giants reaching 100M. They have adapted to grow in almost every situation – dry gullies to dripping forests, sandy soils to deep volcanic earth, sun-blasted plains to snow-capped mountains.

The term “gum tree” or “eucalypt” covers three very closely related genera - Corymbia, Angophora and Eucalyptus. Study groups are still separating them into their correct places so plant labels will show one or the other.

Australian Plant Society Newcastle Group members are enthusiastic plant hunters and observe the rule of “take nothing but photos, leave nothing but footprints”. Eucalypts make great photo subjects with their patterned barks, hanging foliage and displays of blossoms from white to red.

In the Barrington Tops a locally abundant species is Eucalyptus nitens, known as “Shining Gum”. Its trunk is like a pale slender cathedral pillar soaring up to 60M. It is commonly grown in forestry plantations.

“Mallee” type eucalypts sometimes have a single trunk but most grow with multiple slender stems rising from a fire-resistant lignotuber at the base. Mallees can be grown as large shrubs by occasionally lopping the trunk down close to the lignotuber. They will respond by producing lush new growth. The juvenile leaves are often different from adult leaves.

Two mallees are unique to the Hunter region and both are highly endangered species. One is Eucalyptus castrensis, growing to about 8M with smooth grey-bronze bark and white flowers. It is known from only a few hectares scattered around Singleton in the military area. The other is Eucalyptus pumila, known as Pokolbin Mallee, and it grows to about 6M. It is surviving in just one dense stand near Pokolbin.

There are many ornamental gum trees which grow to about 10M high and are suitable for small gardens. Eucalyptus curtisii “Plunketts Mallee” is from Qld and Angophora hispida is from NSW.

The WA species Corymbia ficifolia, the "WA Flowering Gum", finds eastern Australia's soils and weather a bit hard to take. It is much loved for its fabulous blossom ranging from white to deepest burgundy, although most are mid-toned pinks and oranges. In NSW they may live for a while and then drop dead, or maybe just fail to thrive. Ficifolia has been hybridized with a Qld species, Corymbia phtychocarpa, to create a new group of gums for small gardens. They are only available commercially as they are not a naturally occurring species and are grafted onto local rootstocks. Names include words like “splendour”, “crackerjack”, “beauty” and “glory”. Large leathery foliage is covered by a canopy of thickly-clustered white, orange, red or pink blossoms. When they are in full bloom they are all "traffic stoppers" as the blossom display is very striking.