Paper-bark tree – gurrundurrung

What is a paper-bark tree?

Paper-bark trees also know as paper-bark tea trees have pale flaking papery bark, leaves with a strong aroma and brush-like flowers. They are members of the  Melaleuca  genus. In Darug language paper-bark tea tree is  gurrundurrung.

The species growing in Field of Mars Reserve and neighbouring Lane Cove National Park include  Melaleuca decora  – white feather honeymyrtle,   Melaleuca ericifolia  – swamp paper-bark,  Melaleuca linariifolia  – snow in summer,  Melaleuca quinquenervia  – broad-leaved paper-bark and  Melaleuca styphelioides  – prickly-leaved paper-bark.

The name ‘tea tree’ also applies to the genus  Leptospermum.  Leptospermum  species are shrubs with distinctive five-petalled flowers and small round seed pods with five segments. They also have aromatic leaves.

Large old Melaleuca quinquenervia – broad-leaved paper-bark – growing in Sydney Harbour National Park

What do paper-bark trees look like?

Characteristics of the  Melaleuca  species are the layered papery bark on the trunks and flowers that look like bottle-brushes. Each ‘flower’ is actually several clusters of flowers, the visible part being the long fine soft stamens. The fruit form as woody seed capsules clustered along the ‘flower stem’.

Whilst they all have flaking papery bark and aromatic leaves, there are differences between the species.  Melaleuca decora  – white feather honey myrtle – grows to about 7 metres tall and has white or pale cream flowers and narrow leaves, growing along the stem alternately.  Melaleuca ericifolia  – swamp paper-bark – has pale cream flowers and short narrow leaves. It grows densely as a tall shrub or can grow as a tree to about 9 metres tall.  Melaleuca linariifolia  – snow in summer – also has pale cream flowers but longer leaves. It also grows as a shrub or small tree to about 10 metres.

The very spiky  Melaleuca styphelioides  – prickly-leaved paper-bark – has white or pale cream flowers and has short narrow spiky leaves. It can grow to 20 metres tall and has dense foliage.  Melaleuca quinquenervia  – broad-leaved paper-bark – has longer, wider leaves, usually with 5 visible veins running the length of the leaf. It has white or pale cream flowers and can grow to 20 metres tall and 100 years old.

Small spiky leaves of Melaleuca styphelioides – prickly-leaved paper-bark

Grove of planted Melaleuca styphelioides and Melaleuca linariifolia at Field of Mars Reserve

Close-up of the layers of bark on a paper-bark tea tree

Leaves and fruit of Melaleuca quinquenervia – broad-leaved paper-bark. The leaves usually have five long veins.

How are paper-bark trees used by Aboriginal Peoples of the area?

A medicine plant, the aromatic oil in the leaves of paper-bark trees has antiseptic properties and can be used on cuts and abrasions. The leaves can be crushed and rubbed on the forehead or crushed, boiled or burned and inhaled to relieve the symptoms of colds such as headaches, coughs, runny nose and sore throat. Note – the leaves and oil cannot be ingested or eaten.

First used by the Bundjalung Peoples of the northern rivers area of NSW, tea tree oil distilled from  Melaleuca alternifolia  has been commercially produced since 1923 for use by humans as an antiseptic.

Paper-bark tree leaves have medicinal uses. These are the leaves of Melaleuca linariifolia.

The papery bark can be used to wrap food such as fish for baking in a fire. Large thick sheets of paper bark can be used as a roofing material on gunyahs – shelters – providing weather protection and helping to deter mosquitoes.

Because the bark is soft, it can also be used as bedding and to line coolamons when used for carrying a baby. A coolamon is a large shallow wooden bowl.

Layers of the papery bark can be used to wrap food for cooking, as bandages and as bedding.

Where do paper-bark trees grow?

Along the banks of waterways, swamps and the outer edge of salt marshes are the natural habitat of paper-bark trees. In salt marshes, swamp paper-bark trees grow just above the maximum tide mark between salt marsh plants and eucalypts.

Paper-bark trees are often planted as shade trees in large gardens, parks and school grounds.

Paper-bark trees grow naturally on the banks of creeks. These paper-bark trees survive regular flooding and poor water quality of this urban creek in Field of Mars Reserve.

Melaleuca quinquenervia – broad-leaved paper-barks – growing in a coastal swamp forest on the fringe of Myall Lake on the NSW lower north coast

What food and habitats do paper-bark trees provide?

The flowers of paper-bark trees are rich in nectar and used by nectar feeding birds such as rainbow lorikeets and honey eaters, mammals such as possums and flying foxes and invertebrates such as native and introduced bees.

The dense foliage can provide shelter and nest sites for small birds. Spiders build webs amongst the layers of bark.

Spider web in the fold of a piece of paper-bark

What other roles do paper-bark tea trees play in the ecosystem?

The spreading shallow roots of paper-bark trees help to hold the soil and stabilise the banks of creeks, swamps and lakes. They intersect and form a mat-like base. Their roots can stain the water a dark brown colour – like dark tea.

Matted paper-bark tea tree roots stabilising the shore of Myall Lake. Melaleuca quinquenervia – broad-leaved paper-bark trees – grow on the lake’s fringes.

What adaptations do paper-bark trees have?

Adaptations of paper-bark trees relate mainly to their growth and survival in swampy and wet environments. Their root systems are spreading providing stability in wet and soggy soils. Some species have adaptations to mildly saline water and to being water logged such as fibrous roots around the base of the tree which are thought to act as ‘breathing roots’.

The thick bark of paper-bark trees provides protection from fire. The Greek derivation of the word  Melaleuca  is ‘melas’ – black, ‘leukos’ – white, and refers to ‘black fire scars on white trunks’ (Hornsby Shire Council).

How do paper-bark trees reproduce?

Most paper-bark tea trees flower in spring or summer. They are pollinated mainly by insects but also birds and arboreal mammals such as possums.

Following flowering, clusters of woody seed capsules are formed. Each seed pod holds thousands of tiny seeds. The seed pods usually only open during a bushfire or if the plant dies.

The bottle-brush shaped flowers of a Melaleuca decora – white honey myrtle.

Close-up of the clusters of stamens that form the bottle-brush like flowers. The tiny petals are at the base of each group of stamens.

Seed pods forming from the spent flowers of a Melaleuca quinquenervia – broad-leaved paper-bark.

Seed pods of Melaleuca decora – white honey myrtle – each holding thousands of tiny seeds.

What threats do paper-bark trees face and how can we help?

Loss of habitat through clearing and reclamation of swamps result in loss of species and fragmentation. Other impacts include changing water levels and water quality which result in changed soil moisture and chemical composition. Weed invasion is another impact, resulting in inability for seeds to germinate and succeed.

Piles of weeds after being removed from a grove of paper-bark trees along Buffalo Creek in the Field of Mars Reserve.