Genus of crops within the Myrtle household
Melaleuca () is a genus of practically 300 species of crops within the myrtle household, Myrtaceae, generally generally known as paperbarks, honey-myrtles or tea-trees (though the final title can also be utilized to species of Leptospermum).:19 They vary in dimension from small shrubs that not often develop to greater than 16 m (52 ft) excessive, to timber as much as 35 m (115 ft). Their flowers usually happen in teams, forming a “head” or “spike” resembling a brush used for cleansing bottles, containing as much as 80 particular person flowers.
Melaleucas are an essential meals supply for nectarivorous bugs, birds, and mammals. Many are standard backyard crops, both for his or her engaging flowers or as dense screens and some have financial worth for producing fencing and oils comparable to “tea tree” oil. Most melaleucas are endemic to Australia, with just a few additionally occurring in Malesia. Seven are endemic to New Caledonia, and one is discovered solely on (Australia’s) Lord Howe Island. Melaleucas are present in all kinds of habitats. Many are tailored for all times in swamps and boggy locations, whereas others thrive within the poorest of sandy soils or on the sting of saltpans. Some have a large distribution and are frequent, while others are uncommon and endangered. Land clearing, unique myrtle rust, and particularly draining and clearing of swamps threaten many species.
Melaleucas vary in dimension from small shrubs comparable to M. aspalathoides and M. concinna which not often develop to greater than 1 m (3 ft 3 in) excessive, to timber like M. cajuputi and M. quinquenervia, which might attain 35 m (115 ft). (One specimen of M. cajuputi reached 46 m (151 ft)
Many, like M. lineariifolia, are generally known as paperbarks and have bark that may be peeled in skinny sheets, while about 20% of the genus, together with M. bracteata, have exhausting, tough bark and one other 20% have fibrous bark. Each species within the genus is an evergreen, and the leaves fluctuate in dimension from minute and scale-like (M. micromera) to 270 mm (11 in) lengthy (M. leucadendra). Most have distinct oil glands dotted within the leaves, making the leaves fragrant, particularly when crushed.:20–21
Melaleuca flowers are often organized in spikes or heads. Inside the head or spike, the flowers are sometimes in teams of two or three, every flower or group having a papery bract at its base. 5 sepals happen, though these are generally fused into a hoop of tissue and 5 petals that are often small, not showy, and fall off because the flower opens or quickly after. The stamens fluctuate drastically in color, from white to cream or yellow, purple, or mauve with their yellow suggestions (the anthers) contrasting with their “stalks” (filaments).:20–21
The fruit are woody, cup-shaped, barrel-shaped, or nearly spherical capsules, usually organized in clusters alongside the stems. The seeds are generally retained within the fruit for a few years, solely opening when the plant, or a part of it, dies or is heated in a bushfire. In tropical areas, seeds are launched yearly within the moist season.:25–26
Taxonomy and naming
The primary recognized description of a Melaleuca species was written by Rumphius in 1741, in Herbarium amboinense earlier than the current system of naming crops was written. The plant he known as Arbor alba is now generally known as Melaleuca leucadendra. The title Melaleuca was first utilized by Linnaeus in 1767. Many species beforehand generally known as Metrosideros have been then positioned in Melaleuca. In Australia, Melaleuca is the third most numerous plant genus with as much as 300 species.
The genus Callistemon was raised by Robert Brown, who famous its similarity to Melaleuca, distinguishing it solely on the premise of whether or not the stamens are freed from one another, or joined in bundles. Botanists previously, together with Ferdinand von Mueller and Lyndley Craven have proposed uniting the 2 genera however the matter will not be determined. Proof from DNA research means that both Callistemon and another genera be included into Melaleuca or that not less than 10 new genera be created from the current genus.:16–17
In 2014, Lyndley Craven and others proposed, on the premise of DNA proof, that species within the genera Beaufortia, Calothamnus, Conothamnus, Eremaea, Lamarchea, Petraeomyrtus, Phymatocarpus and Regelia be transferred to Melaleuca. The World Guidelines of Chosen Plant Households maintained by the Royal Botanic Gardens, Kew lists Calothamnus and the opposite genera as synonyms of the accepted genus Melaleuca. The transfer has not been adopted by all Australian herbaria with some taxonomists, together with Alex George opposing the transfer.
The title Melaleuca is derived from the Historical Greek μέλας (mélas) that means “darkish” or “black” and λευκός (leukós) that means “white”, apparently as a result of one of many first specimens described had fire-blackened white bark. The frequent title “tea-tree” has been utilized to species within the genera Leptospermum, Melaleuca, Kunzea, and Baeckea as a result of the sailors on the Endeavour used the leaves of a shrub from one in every of these teams as a substitute for tea Camellia sinensis throughout Captain James Prepare dinner’s 1770 voyage to Australia.
Distribution and habitat
Most melaleucas happen naturally solely on the Australian mainland. Eight happen in Tasmania, however solely two are endemic to that island. One (M. howeana) is endemic to Lord Howe Island and 7 are endemic to Grande Terre, the principle island of New Caledonia. A number of tropical species additionally happen in Papua New Guinea, and the distribution of 1 subspecies, Melaleuca cajuputi subsp. cumingiana extends as far north as Myanmar, Thailand, and Vietnam. The southwest of Western Australia has the best density of species, and within the tropical north of the continent, species comparable to M. argentea and M. leucadendra are the dominant species over massive areas.
Melaleucas develop in a spread of soil varieties and lots of tolerate occasional and even everlasting waterlogging. Some species, particularly the South Australian swamp paperbark, M. halmaturorum, thrive in saline soils the place few different species survive. Many are fireplace tolerant, regenerating from epicormic buds or by coppicing, however no melaleucas happen in rainforest and few species happen within the arid zone.:26–31
Melaleuca are largely pollinated by bugs, together with the launched honey bee (Apis mellifera), flies, beetles, wasps and thrips. Birds comparable to lorikeets and honeyeaters in addition to bats usually go to the flowers and are most likely additionally pollinators.:23
Some species of Melaleuca, particularly M. alternifolia, are cultivated for the manufacturing of tea tree oil, and in plantations are vulnerable to a variety of insect pests. Probably the most important of those is the Chrysomelid, Paropsisterna tigrina, however different beetles, cutworm caterpillars (Agrotis species), psyllids, mole crickets (Gryllotalpa), and others trigger important injury. Greater than 100 species of bugs are recognized to feed on melaleucas. Native stands have fewer predators, however tea tree sawfly (Pterygophorus species) and longicorn beetles are sometimes discovered. Melaleucas are additionally vulnerable to myrtle rust (Puccinia psidii) which may end up in injury to comfortable plant materials and the loss of life of extremely vulnerable hosts. Myrtle rust is frequent in japanese Australia, together with Tasmania and has been detected within the Tiwi Islands.
Melaleuca quinquenervia (broad-leaved paperbark) is probably the most damaging of 60 unique species launched to the Florida Everglades to assist drain low-lying swampy areas. Launched within the early 20th century, it has change into a severe invasive species, with damaging results together with the displacement of native species, discount in wildlife habitat, alteration of hydrology, modification of soil, and adjustments in fireplace regimes.
Makes use of
Conventional Aboriginal makes use of
Aboriginal Australians used a number of species of Melaleuca to make rafts, as roofing for shelter, bandages, and meals preparation. “Bee bread” and honey have been collected from the hives of native stingless bees in melaleuca forests within the Northern Territory. The Bundjalung folks historically lived within the space of north-eastern New South Wales the place Melaleuca alternifolia is endemic, and so they handled pores and skin infections by crushing the leaves of that species over pores and skin infections then protecting the world with a heat mudpack.
Melaleuca alternifolia is notable for its important oil which is each antifungal and antibiotic, whereas safely usable for topical functions. That is produced on a business scale and marketed as tea tree oil.
Melaleuca cajuputi is used to provide an identical oil, generally known as cajuput oil, which is utilized in Southeast Asia to deal with quite a lot of infections and so as to add perfume to meals and soaps.
Melaleucas are standard backyard crops, each in Australia and different tropical areas worldwide. The primary to be cultivated have been grown in England from seed in 1771. Some melaleucas are generally cultivated, grown as timber for parks and huge gardens (comparable to Melaleuca leucadendra) or as ornamentals (generally as Callistemon) comparable to M. citrina (Callistemon citrinus), M. hypericifolia and M. wilsonii.
Melaleucas utilized in horticulture
- “Melaleuca“. Vegetation of the World On-line/Kew Science. Retrieved 23 July 2020.
- Brophy, Joseph J.; Craven, Lyndley A.; Doran, John C. (2013). Melaleucas : their botany, important oils and makes use of. Canberra: Australian Centre for Worldwide Agricultural Analysis. ISBN 9781922137517.
- Boland, Douglas J. (2006). Forest timber of Australia (5 ed.). Collingwood, Vic.: CSIRO. p. 612. ISBN 9780643069695.
- Rumphius, Georg (1741). Herbarium amboinense Quantity 2. Amsterdam. Retrieved eight Could 2015.
- “Melaleuca L.” APNI. Retrieved eight Could 2015.
- Barlow, B.A. (1998). “Patterns of differentiation in tropical species of Melaleuca L. (Myrtaceae)”. Proceedings of the Ecological Society of Australia. 15: 239–247.
- Brown, Robert (1814). A Voyage to Terra Australis Quantity 2. London. p. 548. Retrieved eight Could 2015.
- Craven, Lyndley (2006). “New mixtures in Melaleuca for Australian species of Callistemon (Myrtaceae)”. Novon. 16 (4): 468–475. doi:10.3417/1055-3177(2006)16[468:ncimfa]2.0.co;2. Retrieved eight Could 2015.
- “Callistemon – background”. Australian Native Plant Society (Australia). Retrieved eight Could 2015.
- Craven, Lyn A.; Edwards, Robert D.; Cowley, Kirsten J. (30 June 2014). “New mixtures and names in Melaleuca (Myrtaceae)”. Taxon. 63 (3): 663–670. doi:10.12705/633.38.
- “Calothamnus“. World Guidelines of Chosen Plant Households (WCSP). Royal Botanic Gardens, Kew.
- George, Alex S. (August 2015). “Extra Nomenclature Litter” (PDF). Wildflower Society of Western Australia E-newsletter. 53 (3): 7–9. Retrieved 17 August 2015.
- Gledhill, David (2006). The names of crops (4th ed.). Cambridge: Cambridge College Press. p. 254. ISBN 978-0-521-86645-3.
- Moore, Bruce, ed. (2002). The Australian Oxford Dictionary (1999 ed.). South Melbourne, Vic: Oxford College Press. p. 842. ISBN 0195507932.
- Holliday, Ivan (2004). Melaleucas : a area and backyard information (2nd ed.). Frenchs Forest, N.S.W.: Reed New Holland Publishers. pp. 6–9. ISBN 1876334983.
- Southwell, Ian (1999). Southwell, Ian; Lowe, Robert (eds.). Tea tree : The genus Melaleuca. Amsterdam: Harwood Tutorial. pp. 1–2. ISBN 9057024179.
- “Melaleuca L.” Endemia, New Caledonia. Retrieved 25 January 2018.
- Hawkeswood, Trevor J. (1980). “Jewel beetles as pollinators of Melaleuca pauperiflora F.Muell. between Eucla (W.A.) and Koonalda (S.A.)”. The Western Australian Naturalist. 14: 238–239. Retrieved 20 April 2020.
- Campbell, A.J.; Maddox, C.D.A. (1999). Southwell, Ian; Lowe, Robert (eds.). Tea tree : The genus Melaleuca. Amsterdam: Harwood Tutorial. p. 169. ISBN 9057024179.
- “Myrtle rust”. South Wales Authorities Division of Major Industries. Retrieved 29 June 2016.
- Mazzotti, Frank J.; Middle, Ted D.; Dray, F. Allen; Thayer, Dan. “Ecological penalties of invasion by Melaleuca quinquenervia in south Florida wetlands: Paradise broken, not misplaced”. Retrieved eight Could 2015.
- Langeland, Ok.A. “Assist defend Florida’s pure areas from non-native invasive crops”. College of Florida. Retrieved eight Could 2015.
- “Melaleuca quinquenervia“. Smithsonian Marine Station at Fort Pierce. Retrieved eight Could 2015.
- Levitt, Dulcie; Lyon, Ken (1981). Vegetation and folks : aboriginal makes use of of crops on Groote Eylandt. Canberra: Australian Institute of Aboriginal Research. pp. 54–55. ISBN 9780391022058.
- Williams, Cheryll (2010). Medicinal crops in Australia (1 ed.). Dural, N.S.W.: Rosenberg. ISBN 9781877058943.
- Markham, Julie L. (1999). Southwell, Ian; Lowe, Robert (eds.). Tea tree : The genus Melaleuca. Amsterdam: Harwood Tutorial. p. 169. ISBN 9057024179.
- Carson, C. F.; Hammer, Ok. A.; Riley, T. V. (17 January 2006). “Melaleuca alternifolia (Tea Tree) Oil: a Evaluate of Antimicrobial and Different Medicinal Properties”. Scientific Microbiology Opinions. 19 (1): 50–62. doi:10.1128/CMR.19.1.50-62.2006. PMC 1360273. PMID 16418522.
- O’Brien, Peter; Dougherty, Tony (2007). The effectiveness and security of Australian Tea Tree oil (PDF). Barton, A.C.T.: RIRDC. pp. 9–12. ISBN 978-1741515398. Retrieved 19 August 2015.
- Brophy, Joseph J.; Craven, Lyndley A.; Doran, John C. “Melaleuca – Their Botany, Important Oil and makes use of (Preliminaries)” (PDF). Australian Centre for Worldwide Agricultural Analysis. Archived from the unique (PDF) on 28 Could 2015. Retrieved 19 August 2015.
- Doran, John C. (1999). Southwell, Ian; Lowe, Robert (eds.). Tea tree: the genus melaleuca. Amsterdam: Harwood Tutorial. pp. 221–224. ISBN 9057024179.
- Wrigley, John W.; Fagg, Murray (1983). Australian native crops : a guide for his or her propagation, cultivation and use in landscaping (2nd ed.). Sydney: Collins. pp. 351–352. ISBN 0002165759.
- Brophy, Joseph J.; Craven, Lyndley A.; Doran, John C. (2013). Melaleucas : their botany, important oils and makes use of. Canberra: Australian Centre for Worldwide Agricultural Analysis. pp. 34–35. ISBN 9781922137517.
- Media associated to Melaleuca at Wikimedia Commons