Tessellated-bark is broken up into many distinct flakes.It is impregnated with dried kino (a sap exuded by the tree) which gives a dark red or even black colour. Ironbark-is hard, rough, and deeply furrowed.It is usually thick with a spongy texture. Stringybark-consists of long fibres and can be pulled off in long pieces.ĭifferent commonly recognised types of bark include: This allows the tree to grow in less-than-ideal climates, in addition to providing a better chance of recovery from damage sustained to its leaves in an event such as a fire. globulus bark cells are able to photosynthesize in the absence of foliage, conferring an "increased capacity to re-fix internal CO 2 following partial defoliation". The smooth upper bark of the half-barks and that of the completely smooth-barked trees and mallees can produce remarkable colour and interest, for example E. viminalis, the rough basal bark is very ribbony at the top, where it gives way to the smooth upper stems. In some species in this category, for example E. occidentalis-or only in a thick, black accumulation at the base, as in E. Many species are ‘half-barks’ or ‘blackbutts’ in which the dead bark is retained in the lower half of the trunks or stems-for example, E. jensenii) the rough bark is infused with gum resin. In some species (the "ironbarks" such as E. radiata) or more tightly adherent (as in the "boxes" such as E. In some of these species, the fibres in the bark are loosely intertwined (in stringybarks such as E. The remaining species retain the dead bark which dries out and accumulates. These species are known as "smooth barks" and include E. The dead bark may be shed in large slabs, in ribbons or in small flakes. In about half of the species, the dead bark is shed exposing a new layer of fresh, living bark. platypus, showing ‘marlock’ form, MelbourneĪll eucalypts add a layer of bark every year and the outermost layer dies. Įucalyptus trees, including mallets and marlocks, are single-stemmed and include Eucalyptus regnans, the tallest known flowering plant on Earth. Eucalyptus platypus is an example of a marlock. A marlock is a shrub or small tree with a single, short trunk, that lacks a lignotuber and has spreading, densely leafy branches that often reach almost to the ground. Eucalyptus astringens is an example of a mallet. A mallet is a tree with a single thin trunk with a steeply branching habit but lacks both a lignotuber and epicormic buds. The terms " mallet" and " marlock" are only applied to Western Australian eucalypts. surgens growing on coastal cliffs in Western Australia are examples of eucalypt shrubs. Eucalyptus vernicosa in the Tasmanian highlands, E. There is no clear distinction between a mallee and a shrub but in eucalypts, a shrub is a mature plant less than 1 m (3 ft 3 in) tall and growing in an extreme environment.
Trees usually have a single main stem or trunk but many eucalypts are mallees that are multistemmed from ground level and rarely taller than 10 metres (33 feet). In some countries, however, they have been removed because of the danger of forest fires due to their high flammability.ĭescription Size and habit Įucalypts vary in size and habit from shrubs to tall trees. Eucalypts have been grown in plantations in many other countries because they are fast growing and have valuable timber, or can be used for pulpwood, for honey production or essential oils. Many eucalypt species have adapted to wildfire, and resprout after fire or have seeds which survive fire.Ī few species are native to islands north of Australia and a smaller number are only found outside the continent. About three-quarters of Australian forests are eucalypt forests. Most species of Eucalyptus are native to Australia, and every state and territory has representative species. The fruit is a woody capsule commonly referred to as a "gumnut".
Plants in the genus Eucalyptus have bark that is either smooth, fibrous, hard or stringy, the leaves have oil glands, and the sepals and petals are fused to form a "cap" or operculum over the stamens. Along with several other genera in the tribe Eucalypteae, including Corymbia and Angophora, they are commonly known as eucalypts. Most species of Eucalyptus are trees, often mallees and a few are shrubs. Symphyomyrtus Schauer in J.G.C.Lehmann, 1844Įucalyptus ( / ˌ juː k ə ˈ l ɪ p t ə s/) is a genus of more than 700 species of flowering plants in the family Myrtaceae.
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