Trees of Australia Paperbark

The genus Melaleuca is often known as the ‘paper-bark’ and has over 200 recognised species. Melaleuca belongs to the myrtle family Myrtaceae. Melaleucas may be trees or shrubs depending on the species.  Heights range from 2 to 30 metres tall.  Some form sprawling shrubs whilst in more protected areas, others are erect and much taller. Many have thick, whitish bark made up of many papery layers.  The flaky bark can be peeled off in long, wide sheets. The crown is dense with silvery new growth.

The melaleuca is an evergreen plant. The broad, stiff leaves have five to seven veins running from the base to the tip. They are dark-green to grey-green in colour.  Leaves stand out from the stems in a vertical plane and range from 5 to 9cm long, 1 to 3cm wide with a pointed tip. Dense clusters of thick, fluffy flower spikes are produced along the stems. The flowers resemble a bottlebrush. The flower spike grows out into a leaf-bearing twig. There is a variety of colours from white, yellow, pink, red and even a greenish shade. Grey-brown, woody seed capsules crowd together on the twigs and contain numerous tiny seeds.

Melaleuca go by a number of different names. The larger species are known as ‘paperbarks’ because of the type of bark. Smaller ones are known as honey myrtles. Ti-tree or tea tree is another common name although tea tree may also be used for members of the Leptospermum genus. Natural habitats for melaleucas include open forest, woodland or shrubland, more commonly along watercourses and the edges of swamps. They are popular garden plants and thrive in Australia and worldwide.

The paperbark had many uses for the indigenous Australians. It is soft and flexible and was used to line coolamons (baskets or cradles used to hold infants), as a sleeping mat, a bandage and to cover humpies.  It was also used to repair holes in canoes and as a temporary raincoat. When wrapped around food and placed in an underground oven, the paperbark doesn’t ignite and the moistness of the food is preserved.  Some tribes would wrap the bodies of the deceased in melaleuca bark before placing them in caves or rock clefts. In some areas, the trunks of large specimens were utilised as canoes. An effective topical ointment with antibacterial and anti-fungal properties is made from melaleuca (tea tree) oil extracted from Melaleuca alternifolia. Melaleuca oils are also used in remedies used to treat bacterial and fungal infections in pet fish.

Melaleucas have a fine mat of roots which aid in re-vegetation work along river banks and on unstable slopes. They have good resistance to cyclonic winds. Melaleuca quinquenervia (broad-leaved paperbark) was introduced into Hawaii and the everglades of Florida in an effort to help drain swampy areas. Unfortunately conditions were so conducive to its growth that it has now been declared a noxious weed. It is highly flammable and spreads aggressively. It has displaced native vegetation and formed dense thickets.

Melaleuca irbyana (swamp tea tree) forms a type of forest found only in south-east Queensland. The trees form thickets under a canopy of eucalyptus which may comprise ironbarks, grey box or forest red gum. The swamp tea-tree forests grow on poorly draining clay soils and provide shelter and nesting sites for birds whilst fallen logs are utilised by reptiles and small animals.

Melaleuca cuticularis (saltwater paperbark) is native to Western Australia and tolerates reasonably saline conditions.  This is a ghostly tree, gnarled and twisted. The fruit are cup-shaped but appear star-shaped from above. The saltwater paperbark differs from other melaleucas by its opposite leaf arrangements, the brown bracts at the base of the flowers and the larger, star-shaped fruits.

The melaleucas are another of the fascinating plant species that make up the vegetation of Australia.

Sources:
https://www.epa.qld.gov.au/register/p00292aa.pdf
http://www.environment.gov.au/biodiversity/threatened/publications/swamp-tea-tree-forest.html