Leptospermum lanigerum | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Myrtales |
Family: | Myrtaceae |
Genus: | Leptospermum |
Species: | L. lanigerum |
Binomial name | |
Leptospermum lanigerum (Sol. ex Ait.) Sm. | |
Leptospermum lanigerum, commonly known as the woolly teatree, [1] is a small tree or medium shrub from the plant family Myrtaceae . [2] Its common name derives from the conspicuously hairy capsules produced as fruit, along with the fine, silky hairs present on branches and leaves. L. lanigerum is widespread in many habitats, particularly in waterlogged areas such as moist, sandy coastal heaths, on river banks, riparian scrub, woodlands and on the fringe of montane grasslands. This species is endemic to Australia, with native populations occurring in New South Wales, South Australia, Tasmania and Victoria. [3]
Flowers possess the typical characteristics present within the genus Leptospermum ; five free, white petals, many stamens and five small sepals; although the most distinctive feature is the persistent hairy capsules and the silvery appearance of mature foliage. [4]
L. lanigerum is common and widespread throughout Australia, occurring both as natural populations and cultivated varieties. This species has been used for many years by Indigenous Australians, and is a popular garden plant today. [5]
This small tree to medium-sized shrub is variable in size and shape and present in a number of different forms. Plants can grow as large, spreading or erect shrubs up to 3 metres (9.8 ft) high by 3 metres (9.8 ft) across, or very compact, columnar shrubs, up to 3 m high and 1 metre (3.3 ft) across. [6] L. lanigerum also grows as a slender tree up to 18 metres (59 ft) tall in montane habitats in Tasmania. [7]
Leaves are usually alternately arranged along the stem, oblong in shape and with slightly rolled margins. [2] Leaves vary in size from 4–20 millimetres (0.16–0.79 in), with new growth usually covered in small, soft, silky hairs. [6] These hairs usually cause the foliage to appear silvery grey, however leaves can vary in colour from silvery grey to dark green, or occasionally possess a glossy upper surface. [8] Like all species in the family Myrtaceae, L. lanigerum leaves are dotted with small oil containing glands, and when crushed emit a strong, characteristic aroma. [9] These oil glands allow for easy identification, and detailed analysis of the oils has assisted in the classification and taxonomy of species within the genus Leptospermum . [10] [11]
Leptospermum lanigerum bears the characteristic flowers present within the genus Leptospermum : five distinctly separate, white petals, five small sepals, numerous stamens, along with inferior ovaries. [4] Receptacles and petals grow small soft hairs, with flowers usually measuring about 18mm in diameter. [12] The stamens usually occur in bundles of seven. [8] Numerous flowers are produced either in late spring, early summer or sporadically throughout the year, situated terminally on short side branches. [2] These flowers are mostly bisexual, however L. lanigerum is an andromonoecious species as plants also produce some functionally male flowers. [13]
Distinctly hairy when first produced, capsules are usually persistent, each with 4–5 compartments and around 5–10 millimetres (0.20–0.39 in) in diameter. These capsules are situated singularly on short, terminal side branches, distinguishable from Melaleuca spp. whose capsules clasp the stem in distinctive clusters. [14] Encasing seeds in tough, woody capsules provides some protection from damage by predators or insulation from disturbances such as fire. [15] Extreme desiccation or fire is needed, however, to open these capsules, allowing seeds to be released to germinate in the ash enriched seed bed after the first rains following the fire. [16]
Leptospermum lanigerum has smooth, light brown, fibrous and papery bark that comes away from the trunk in long strips when removed. This bark helps provide some protection to the trunk and epicormic buds from fire, allowing the tree to potentially grow back when burnt. The bark is very similar to other Leptospermum species. [16]
The name Leptospermum (lep-toh-SPERM-um) is derived from the Greek words leptos, meaning slender, and sperma, meaning seed. This refers to the very slender seed shape found in the first species of the genus to be described, L. scoparium . The species name, lanigerum, is named using the Latin word for wool-bearing, describing the silky hairy leaves and hairy buds, shoots and young capsules. The common names for this species, 'woolly tea-tree' or sometimes 'silky tea-tree', are also a result of these distinctive features. [17]
The original collection of these species held at the Royal Botanical Gardens in Kew was first described by William Aiton in 1789 as Philadelphus laniger. Sir James Smith, however, later transferred the plant to the genus Leptospermum . [18] The species name has undergone a number of changes in the past, however is known today as Leptospermum lanigerum (Sol. ex Aiton) Smith. [7]
Species within the genus Leptospermum are usually referred to as 'tea-trees'. This name was first used by the crew of Captain Cook, who brewed a tea from the aromatic leaves in Australia and New Zealand, as they believed it would protect them from scurvy. [17] The spelling 'ti-tree' often occurs in literature, however this is incorrect. [19] The naming of the essential oil 'Tea-tree oil' is another common misuse of the name, as Tea-tree oil actually comes from the leaves of Melaleuca alternifolia , not a Leptospermum species. [17]
Leptospermum is a genus within the family Myrtaceae, a large and complex family very prominent within Australian vegetation. Other conspicuous genera within this family are Eucalyptus (eucalypts) and Melaleuca (bottlebrushes). [20] There are 83 species within Leptospermum, of which 79 are endemic to Australia. [19]
Leptospermum lanigerum is endemic to Australia, mainly distributed within the south eastern states. Native populations are found in eastern South Australia, across Victoria and southern New South Wales, as well as the whole of Tasmania. [3] Plants are common and widespread, predominantly found in wet, swampy areas and along river banks, sandy coastal heaths or within woodlands. [2] L. lanigerum is occasionally found growing in cool temperate rainforest in western Tasmania, however is a doubtful true rainforest species due to the need for disturbances such as fire to release seed. [21] The hardy nature and preferred habitat of this plant makes it useful in riparian restoration and stream bank stabilisation, as they thrive in swampy areas where many other species do not. [2]
In Tasmania, L. lanigerum is a key swamp forest species. Swamp forests form in flat, poorly drained sites and contain a closed tree canopy made from sclerophyllous species of the genera Leptospermum , Acacia and Melaleuca . [22] In Tasmania, L. lanigerum forms tall, dense stands, up to 18m in height. In other Australian states, individuals mainly exist as short, thick shrubs. [7]
Although this species is mainly present at low altitudes, some individuals also grow among sub-alpine vegetation and along the edge of montane grasslands. [23] L. lanigerum is an adaptable species able to adjust to varying aspects and soil types, and although prefers wet areas can grow successfully in drier soil. [2]
L. lanigerum has a very specific relationship with fire. Like many other species within the family Myrtaceae, the seeds of L. lanigerum are encased in woody capsules and often remain on the tree for a number of years after reaching maturity. To be released, capsules must be subjected to fire or some other disturbance. [24] In the days after fire, the ash enriched seed bed along with a little rain provides good conditions for seeds to germinate. The intensity of the fire is important, as too much heat can destroy the seeds as well as the capsules. [15]
Trees can also grow back after a fire, due to the lignotubers and epicormic buds protected by the thick bark. [25] In some cases, where trees are tightly packed, the fire destroys only the main branches leaving the underground portions and protected trunks of the plants to survive. As plants grow back after a fire, other species can take advantage of the light gaps created, leading to a thick mixture of tea-tree, cutting grass and species such as Bauera . [26]
Leptospermum species are pollinated by insects, usually beetles. Each flower contains sweet nectar within the centre which acts as an attractant to beetles. These beetles then carry pollen on all parts of their body, mainly head and legs, to other flowers. [27] The nectar, along with the insects present, also attracts other animals such as birds, making Leptospermum species and other Myrtaceae genera popular garden plants. [28]
Seed dispersal of L. lanigerum is limited, with seeds usually falling to the ground after fire. Dispersal can also occur through wind or water, or transport by insects such as ants. Ants also act as pre-dispersal seed predators however, destroying the capsules whilst still attached to the plant and eating the seeds. L. lanigerum is one of the Leptospermum species most affected by ant predation. [29]
Most Myrtaceae species (including the genus Leptospermum) are mycorrhizal, forming relationships with fungi to assist in increasing root surface area for greater uptake in nutrients. [28] The extent to which this relationship exists is unknown however, with little research available. [30]
Leptospermum lanigerum is a potentially highly susceptible host species to the pathogen Phytophthora ramorum . This pathogen currently causes widespread damage to gardens, nurseries and natural habitats in America and Europe, and although is not currently present in Australia, has been identified as a potential problem that may have widespread effects throughout Australia in the future. [31]
A number of insects also act as pests and parasites. The Webbing Caterpillar causes damage to many young Leptospermum species, using webbing to matt the leaves together and deposit droppings inside. Scale insects can suck the sap from stems and leaves and secrete a substance that causes sooty mould to grow, blackening the foliage. [32]
Leptospermum lanigerum is an adaptable species that can tolerate most soils and aspects. Plants are often propagated from seedlings or cuttings and sold in nurseries for garden use. [18] This species is a popular garden plant, due to its attractive flowers and adaptability. Three main forms are known; a large, spreading or erect shrub to 3 m high and 3 m across, a compact columnar shrub to 3 m high by 1 m wide and a slender tree up to 18 m tall (only in Tasmania). [6]
Leptospermum lanigerum was the first Leptospermum species to be brought into cultivation in March 1773. Captain Tobias Furneaux, of HMS Adventure, collected seed from Adventure Bay, Tasmania, as part of Captain James Cook's second visit to the South Seas. This seed was recorded as being in cultivation at the Royal Botanic Gardens, Kew, in 1774. [18]
Indigenous Australians had many uses for L. lanigerum, including the creation of kangaroo spears and double barbed spears from L. lanigerum wood. [33] Young shoots and stems of many Leptospermum species were also used medicinally to treat urinary disorders. [5]
Although not widely drunk today, it is recorded that many Leptospermum species were used as a tea substitute by European settlers. Captain Cook's crew also brewed tea as they believed it would help prevent diseases such as scurvy. [3]
Melaleuca is a genus of nearly 300 species of plants in the myrtle family, Myrtaceae, commonly known as paperbarks, honey-myrtles or tea-trees. They range in size from small shrubs that rarely grow to more than 16 m (52 ft) high, to trees up to 35 m (115 ft). Their flowers generally occur in groups, forming a "head" or "spike" resembling a brush used for cleaning bottles, containing up to 80 individual flowers.
Leptospermum scoparium, commonly called mānuka, mānuka myrtle, New Zealand teatree, broom tea-tree, or just tea tree, is a species of flowering plant in the myrtle family Myrtaceae, native to New Zealand and south-east Australia. Its nectar produces Mānuka honey.
Leptospermum is a genus of shrubs and small trees in the myrtle family Myrtaceae commonly known as tea trees, although this name is sometimes also used for some species of Melaleuca. Most species are endemic to Australia, with the greatest diversity in the south of the continent, but some are native to other parts of the world, including New Zealand and Southeast Asia. Leptospermums all have five conspicuous petals and five groups of stamens which alternate with the petals. There is a single style in the centre of the flower and the fruit is a woody capsule.
Beaufortia is a genus of woody shrubs and small trees in the family Myrtaceae and is endemic to Southwest Australia. The genus Beaufortia is closely related to Melaleuca, Calothamnus, Regelia and several others, differing mainly in the way the anthers are attached to the stalks of the stamens, and in the way they open to release their pollen. Beaufortia anthers are attached at one end and open by splitting at the other.
Melaleuca armillaris, commonly known as bracelet honey myrtle, is a plant in the myrtle family, Myrtaceae, and is native to South Australia, Victoria and Tasmania in south-eastern Australia. It is a hardy, commonly grown species, often used as a fast-growing screen plant, but it also has the potential to become a weed. It has become naturalised in Western Australia and parts of Victoria. In its natural state, it grows on coastal cliffs and along estuaries.
Melaleuca linariifolia is a plant in the myrtle family Myrtaceae, and is endemic to eastern Australia. It is commonly known as snow-in-summer, narrow-leaved paperbark, flax-leaved paperbark and in the language of the Gadigal people as budjur. A hardy plant, it flowers prolifically in late spring or summer, making it a popular garden shrub or small tree in temperate places. Melaleuca trichostachya is a similar species but its leaves are arranged differently and the fruits have projecting valves.
Leptospermum laevigatum, commonly known as the coast tea tree, is a species of shrub or small tree that is endemic to south-eastern Australia, but has been widely introduced in other places where it is often considered to be a weed. It has thin, rough bark on the older stems, narrow egg-shaped leaves, relatively large white flowers and flat topped fruit that is shed shortly after reaching maturity.
Eremaea is a genus of woody shrubs and small trees in the family Myrtaceae and is endemic to the south-west of Western Australia. Little study of the genus as a whole had been undertaken until Roger Hnatiuk researched Eremaea and published a paper in 1993, A revision of the genus Eremaea (Myrtaceae) in Nuytsia. The first species to be described was Eremaea pauciflora in 1837 and by 1964, the number of species known had increased to 12. Hnatiuk recognised 16 species, 5 subspecies and a number of varieties.
Melaleuca rhaphiophylla, commonly known as swamp paperbark is a plant in the myrtle family, Myrtaceae and is endemic to the south west of Western Australia. It has narrow, needle-like leaves and profuse spikes of white or yellowish flowers at variable times throughout the year. As its common name suggests, it is usually found in salt marshes, or swamps or along watercourses and occurs over wide areas of the south-west.
Melaleuca viridiflora, commonly known as broad-leaved paperbark, is a plant in the myrtle family Myrtaceae, and is native to woodlands, swamps and streams in monsoonal areas of northern Australia and New Guinea. It is usually a small tree with an open canopy, papery bark and spikes of cream, yellow, green or red flowers.
Melaleuca hypericifolia, commonly known as hillock bush, is a plant in the myrtle family, Myrtaceae, genus Melaleuca and is endemic to New South Wales in Australia. It has large, orange to red flower spikes and consequently is a commonly cultivated species. In 1797, James Edward Smith described the plant as:
Leptospermum nitidum, commonly known as shiny tea-tree, is a species of compact shrub that is endemic to Tasmania. It has crowded, aromatic, elliptical leaves, white flowers about 15 mm (0.59 in) in diameter and fruit that remain on the plants until it is burned or dies.
Leptospermum continentale, commonly known as prickly tea-tree, is a species of slender, straggling shrub that is endemic to south-eastern Australia. It has sharp-pointed, narrowly egg-shaped leaves, white flowers arranged singly in leaf axils and woody fruit that remains on the plant when mature.
Leptospermum rupestre, commonly known as alpine tea-tree or prostrate tea-tree, is a flowering shrub in the myrtle family, Myrtaceae. It is endemic to Tasmania. In alpine areas it assumes a prostrate habit while in subalpine areas it appears as a large shrub.
Melaleuca pallida, commonly known as lemon bottlebrush, is a plant in the myrtle family, Myrtaceae and is endemic to eastern Australia. It is an upright shrub with thin, spreading branches, silvery new growth and pale yellow, sometimes pinkish bottlebrush flowers.
Leptospermum fastigiatum is a shrub that is endemic to the south-west of Australia. It has narrow egg-shaped leaves with the narrower end towards the base and a small point on the tip, white flowers arranged singly or in pairs on short side shoots and small fruit that fall off when mature.
Leptospermum sericeum, commonly known as the silver tea tree, is a species of shrub that is endemic to the south-west of Western Australia. It has thin, firm bark, egg-shaped leaves with the narrower end towards the base, relatively large, pink flowers and fruit that fall from the plant with the seeds. It grows in windswept rock crevices near Esperance.
Leptospermum glaucescens, commonly known as the blue-green tea tree or smoky tea tree, is a species of shrub or small tree that is endemic to Tasmania. It has elliptical to egg-shaped leaves that are often greyish green, white flowers about 15 mm (0.59 in) in diameter arranged in consecutive leaf axils and fruit that remain on the plant for some time after maturity.
Leptospermum multicaule, commonly known as the silver tea-tree, is a species of shrub that is endemic to south eastern Australia. It has linear, narrow elliptical or narrow egg-shaped leaves, white or pink flowers usually borne singly on short side shoots, and fruit the falls from the plant soon after the seeds are released.
Leptospermum riparium, commonly known as riverine tea-tree, is a species of straggling shrub that is endemic to Tasmania. It has flaky bark, crowded, lance-shaped leaves with the narrower end towards the base, relatively large white flowers and fruit that remain on the plant when mature. It grows on river banks in rainforest.