Botanical name: Eucalyptus
Botanical name: Eucalyptus
The eucalypts (Eucalyptus) are a huge and diverse group of trees and shrubs in the myrtle family. Eucalypts are strongly associated with Australia, as almost all these species are native to that continent. Many species are of great commercial importance to humans, harvested for timber or pulpwood, used as a source of nectar for bees, or planted ornamentally. Though many eucalypts are relatively small, the genus also boasts some truly massive species – one Mountain Ash (E. regnans), for instance, holds the record for being the second tallest tree in the world, having grown to a staggering 100 m tall.
Species of Eucalypts
It is a straight erect tree, often around 40 m tall, with rough bark on the trunk and base of larger branches, its upper bark peels away in long "ribbons" which can collect on the branches and surrounding ground. Occasionally it can attain very large sizes. A tree with a recorded diameter of 3.27 metres is located at Woodbourne in Marlborough, New Zealand.
Eucalyptus alba is a tree which grows to a height of 5 to 18 m (16 to 59 ft) with a spreading crown 5 to 15 m (16 to 49 ft) wide. The trunk is often bent and has smooth pinkish red to white or cream-coloured powdery bark. The leaves on young plants are arranged alternately egg-shaped to more or less round 10–20 cm (3.9–7.9 in) long and 8–12 cm (3.1–4.7 in) wide. The adult leaves are egg-shaped to lance-shaped 5–12 cm (2.0–4.7 in) long and 5–8 cm (2.0–3.1 in) wide with both sides a similar shade of green. The flower buds are arranged in groups of seven on a peduncle 4–14 mm (0.2–0.6 in) long. The buds are oval to more or less spherical with an operculum 3–5 mm (0.1–0.2 in) long and 4–7 mm (0.2–0.3 in) wide similar in dimensiont to the floral cup. White flowers appear from summer to fall and are sometimes profuse. The fruit are cone-shaped to hemispherical 4–7 mm (0.2–0.3 in) long and 5–8 mm (0.2–0.3 in) wide. The related Eucalyptus bigalerita is similar in appearance but has larger leaves buds and seed pods and is found in alluvial flats.
Forest red gum
Forest red gum hails from Australia and New Guinea. It regularly grows to a height of 50 m and produces useful hardwood. Forest red gum leaves are a common source of eucalyptus oil. The oil is used in scented products but is potentially toxic if swallowed.
Red box (Eucalyptus polyanthemos) is a tree that can grow to 20 m tall. It has round to oval, grayish green leaves and a box-shaped trunk. Foliage is fragrant and evergreen. Blooms in early spring with small, white flowers. Thrives in full sun with medium, well-drained soil. Once established, it is drought tolerant.
Argyle apple (Eucalyptus cinerea) is an evergreen tree that will grow from 6 to 15 m tall and 6 to 12 m wide. Its aromatic foliage is silver-gray and resembles large coins. It blooms profusely in spring with clusters of white flowers. It will be the focal point of any garden with its beautiful bark and leaves. Thrives in full sun with dry to medium moist, well-drained soil. It is drought tolerant.
Tasmanian blue gum
Tasmanian blue gum (Eucalyptus globulus) is an evergreen tree that can grow to over 61 m tall. Blooms from fall to spring with yellowish white flowers. Flower buds have a warty cap that falls off to release the numerous brush-like stamens. Attracts bees hummingbirds and other pollinators. Grows in full sun and is a great specimen for parks and city courtyards.
River red gum
River red gum (Eucalyptus camaldulensis) is a flowering tree that is iconic and widespread in Australia. River red gum is native and endemic to Australia. This species provides shade from the intense heat in Australia, and is planted alongside bodies of water throughout the continent. River red gum is named for its red-colored wood, which is rot-resistant and popularly used as firewood.
Apple box is an Australian eucalypt. A highly prized honey is produced by bees that feed on this tree's flowers. Its species name honors the noted Australian education officer Frederick Bridges (1840–1904). This tree produces an unusually soft wood less suited for firewood and timber than that of other eucalypts.
Rainbow gum is a unique eucalyptus with attractive multicolored bark that more than justifies its name. This fast-growing tree is too large for most gardens, growing to 75 meters, but it makes an attractive addition to parks and larger gardeners. It is also an important pulp wood tree, grown commercially for use in paper production.
Swamp mahogany (Eucalyptus robusta) is an evergreen tree that can grow from 20 to 30 m tall. It blooms from spring to summer with creamy white flowers. Native to Australia the broad leaves of the tree are an important food source for the koala bear. Its timber is used for firewood and construction. Commonly found growing in swamps or waterlogged areas it has thick sponge-like bark.
The cider gum is a hardy evergreen tree that can be grown as a sound barrier and privacy screen. Juvenile branches are often used in cut floral arrangements for their sweet aroma. These trees are easy to grow, drought tolerant, and deer resistant.
Jounama snow gum
Jounama snow gum (Eucalyptus pauciflora) is an attractive evergreen tree highly valued as a specimen tree for its peculiar twisted trunk and two-colored peeling bark. This tree was named pauciflora, which means few-flowered, but this is misleading, possibly due to damage to specimens in transport, since it produces many flowers. The tree is easy to grow and care for and prefers neutral or slightly acid soils.
Wandoo (Eucalyptus wandoo) is a West Australian native tree described by William Faris Blakely in 1934. It was named Wandoo after the Noongar Aboriginal name for the tree. This tree produces a very dense wood that is valued in the construction industry for heavy-duty uses like railway sleepers. Today this tree is not grown, commercially but it was once harvested for the tannin in its wood and bark