''Hibiscus tiliaceus'', commonly known as the sea hibiscus or coast cottonwood, is a species of

flowering A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism ...

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

in the mallow family,

Malvaceae Malvaceae, or the mallows, is a family of flowering plants estimated to contain 244 genera with 4225 known species. Well-known members of economic importance include okra, cotton, cacao and durian. There are also some genera containing familiar ...

, with a

pantropical A pantropical ("all tropics") distribution is one which covers Tropics, tropical regions of both hemispheres. Examples of species include caecilians, modern sirenians and the plant genera ''Acacia'' and ''Bacopa''. ''Neotropical'' is a zoogeogra ...

distribution along coastlines. It has also been introduced to

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

and

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. It has been debated whether this species is native or introduced to

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

Names

Common names include sea hibiscus, beach hibiscus, coastal (or coast) hibiscus, coastal (or coast) cottonwood, green cottonwood, native hibiscus, native rosella, cottonwood hibiscus, kurrajong, sea rosemallow and dhigga ( Maldivian). The plant was introduced by

Austronesian peoples The Austronesian peoples, sometimes referred to as Austronesian-speaking peoples, are a large group of peoples in Taiwan, Maritime Southeast Asia, Micronesia, coastal New Guinea, Island Melanesia, Polynesia, and Madagascar that speak Austro ...

that voyaged across Southeast Asia and Oceania as a source of wood and fibre. This is reflected in the names of the plant as spoken in many related languages spoken in those regions including ''balibago'' ( Tagalog), ''malobago'' ( Bikol), ''malabago'' or ''malbago'' ( Cebuano – Southern), ''maribago'' ( Cebuano – Northern), ''lambago'' (Cebuano - Cagayan de Oro), ''waru'' ( Javanese), ''baru'' or ''bebaru'' (

Malay Malay may refer to: Languages * Malay language or Bahasa Melayu, a major Austronesian language spoken in Indonesia, Malaysia, Brunei and Singapore ** History of the Malay language, the Malay language from the 4th to the 14th century ** Indonesi ...

), ''pagu'' (

Chamorro Chamorro may refer to: * Chamorro people, the indigenous people of the Mariana Islands in the Western Pacific * Chamorro language, an Austronesian language indigenous to The Marianas * Chamorro Time Zone, the time zone of Guam and the Northern Mar ...

), ''hau'' ( Hawaiian), ''fau'' ( Samoan), ''purau'' ( Tahitian), and vau tree. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

, ''"tiliaceus"'', refers to its resemblance of the leaves to those of the related ''

Tilia ''Tilia'' is a genus of about 30 species of trees or bushes, native throughout most of the temperateness, temperate Northern Hemisphere. The tree is known as linden for the European species, and basswood for North American species. In Britain a ...

'' species.

Distribution and habitat

''Hibiscus tiliaceus'' has a worldwide distribution. In the

Old World The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by the ...

and

Oceania Oceania (, , ) is a region, geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern Hemisphere, Eastern and Western Hemisphere, Western hemispheres, Oceania is estimated to have a land area of ...

, it is a common

coast The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in n ...

al plant in most of tropical

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

South Asia South Asia is the southern subregion of Asia, which is defined in both geographical and ethno-cultural terms. The region consists of the countries of Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka.;;;;;;;; ...

(including the

Maldives Maldives (, ; dv, ދިވެހިރާއްޖެ, translit=Dhivehi Raajje, ), officially the Republic of Maldives ( dv, ދިވެހިރާއްޖޭގެ ޖުމްހޫރިއްޔާ, translit=Dhivehi Raajjeyge Jumhooriyyaa, label=none, ), is an archipelag ...

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

, parts of

East Asia East Asia is the eastern region of Asia, which is defined in both geographical and ethno-cultural terms. The modern states of East Asia include China, Japan, Mongolia, North Korea, South Korea, and Taiwan. China, North Korea, South Korea and ...

(as far north as central

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

, where it reaches its northernmost extent), eastern and northern

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

, and much of the

Pacific Islands Collectively called the Pacific Islands, the islands in the Pacific Ocean are further categorized into three major island groups: Melanesia, Micronesia, and Polynesia. Depending on the context, the term ''Pacific Islands'' may refer to one of se ...

, including

(where its establishment status is uncertain). It has also been introduced to

. A separate variety, var. ''pernambucensis'' (formerly considered a separate species, ''H. pernambucensis''), is native to the tropical

New World The term ''New World'' is often used to mean the majority of Earth's Western Hemisphere, specifically the Americas."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. 3 ...

, including

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

, the

Caribbean The Caribbean (, ) ( es, El Caribe; french: la Caraïbe; ht, Karayib; nl, De Caraïben) is a region of the Americas that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Se ...

, and much of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

. This variety has also been introduced to

. It is uncertain if the species is native to Hawaii, as it may have been introduced by the

Polynesia Polynesia () "many" and νῆσος () "island"), to, Polinisia; mi, Porinihia; haw, Polenekia; fj, Polinisia; sm, Polenisia; rar, Porinetia; ty, Pōrīnetia; tvl, Polenisia; tkl, Polenihia (, ) is a subregion of Oceania, made up of ...

ns. It is considered native by

Plants of the World Online Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...

, but the IUCN considers it of uncertain status. ''Hibiscus tiliaceus'' can be found at elevations from sea level to in areas that receive of annual rainfall. It is commonly found growing on

beach A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc shel ...

es, by

rivers A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

and in

mangrove A mangrove is a shrub or tree that grows in coastal saline water, saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evoluti ...

swamp A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in ...

s. Sea hibiscus is well adapted to grow in coastal environment in that it tolerates

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...

and waterlogging and can grow in

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical form ...

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of s ...

coral sand Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secre ...

marl Marl is an earthy material rich in carbonate minerals, clays, and silt. When hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. Marl makes up the lower part o ...

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, and crushed

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

. It grows best in slightly

acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

ic to

alkali In chemistry, an alkali (; from ar, القلوي, al-qaly, lit=ashes of the saltwort) is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a ...

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

s ( pH of 5–8.5).

Cotton Tree, Queensland Cotton Tree is a coastal neighbourhood within the suburb of Maroochydore in the Sunshine Coast Region, Queensland, Australia. Geography Although not officially bounded, Cotton Tree is generally recognised as being bounded by the Maroochy River ...

, Australia is named for the plant.

Description

''Hibiscus tiliaceus'' reaches a height of , with a trunk up to in diameter. The

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s of ''H. tiliaceus'' are bright yellow with a deep red center upon opening. Over the course of the day, the flowers deepen to orange and finally red before they fall. The branches of the tree often curve over time. The leaves are heart shaped and deep red in the var. rubra.

Uses

The wood of ''H. tiliaceus'' has a

specific gravity Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water (molecule), wa ...

of 0.6. It has been used in a variety of applications, such as seacraft construction,

firewood Firewood is any wooden material that is gathered and used for fuel. Generally, firewood is not highly processed and is in some sort of recognizable log or branch form, compared to other forms of wood fuel like pellets or chips. Firewood can ...

, and

wood carving Wood carving is a form of woodworking by means of a cutting tool (knife) in one hand or a chisel by two hands or with one hand on a chisel and one hand on a mallet, resulting in a wooden figure or figurine, or in the sculptural ornamentation ...

s. It is easy to plane and turns well, so it is regarded by many as a high quality furniture wood. Plant fibers taken from the stems have traditionally been used in

rope A rope is a group of yarns, plies, fibres, or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than similarly ...

making, while its bark has been used like cork, in sealing cracks in boats. The bark and roots may be boiled to make a cooling tea to cool

fever Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...

s, and its young leafy

shoot In botany, a plant shoot consists of any plant stem together with its appendages, leaves and lateral buds, flowering stems, and flower buds. The new growth from seed germination that grows upward is a shoot where leaves will develop. In the spri ...

s may be eaten as vegetables.

Native Hawaiians Native Hawaiians (also known as Indigenous Hawaiians, Kānaka Maoli, Aboriginal Hawaiians, First Hawaiians, or simply Hawaiians) ( haw, kānaka, , , and ), are the indigenous ethnic group of Polynesian people of the Hawaiian Islands. Hawaii ...

used the wood to make '' iako'' (spars) for ''waa'' (

outrigger canoe Outrigger boats are various watercraft featuring one or more lateral support floats known as outriggers, which are fastened to one or both sides of the main hull. They can range from small dugout canoes to large plank-built vessels. Outrigger ...

s), ''mouo'' (

fishing net A fishing net is a net used for fishing. Nets are devices made from fibers woven in a grid-like structure. Some fishing nets are also called fish traps, for example fyke nets. Fishing nets are usually meshes formed by knotting a relatively thin ...

floats), and ''au koi'' (

adze An adze (; alternative spelling: adz) is an ancient and versatile cutting tool similar to an axe but with the cutting edge perpendicular to the handle rather than parallel. Adzes have been used since the Stone Age. They are used for smoothing ...

handles). ''Kaula ilihau'' (cordage) was made from the

bast fiber Bast fibre (also called phloem fibre or skin fibre) is plant fibre collected from the phloem (the "inner bark", sometimes called "skin") or bast surrounding the stem of certain dicotyledonous plants. It supports the conductive cells of the phlo ...

s. ''Hau'' would be used to make '' ama'' (canoe floats) if ''

wiliwili Wiliwili (''Erythrina sandwicensis''), is a species of tree in the pea family, Fabaceae, that is endemic to the Hawaiian Islands. It is the only species of '' Erythrina'' that naturally occurs there. It is typically found in Hawaiian tropical d ...

'' (''Erythrina sandwicensis'') was unavailable. ''Hibiscus tiliaceus'' is widely used in Asian countries as a subject for the art of

bonsai Bonsai ( ja, 盆栽, , tray planting, ) is the Japanese art of growing and training miniature trees in pots, developed from the traditional Chinese art form of ''penjing''. Unlike ''penjing'', which utilizes traditional techniques to produce ...

, especially Taiwan. The finest specimens are taken from

Kenting National Park Kenting National Park (), commonly known as Kenting (), is a national park located on the Hengchun Peninsula of Pingtung County, Taiwan, covering Hengchun, Checheng, and Manzhou Townships. Established on 1 January 1984, it is Taiwan's oldest a ...

. Lending itself to free

grafting Grafting or graftage is a horticultural technique whereby tissues of plants are joined so as to continue their growth together. The upper part of the combined plant is called the scion () while the lower part is called the rootstock. The succ ...

, the leaf size is reduced fairly quickly. Its leaves are also used in cooking, as trays for steamed rice cakes ( 粿). In

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

''H. tiliaceus'' is also used for fermenting

tempeh Tempeh or tempe (; jv, ꦠꦺꦩ꧀ꦥꦺ, témpé, ) is a traditional Indonesian food made from fermented soybeans. It is made by a natural culturing and controlled fermentation process that binds soybeans into a cake form. A fungus, ''Rhizopus ...

. The undersides of the leaves are covered in downy hairs known technically as trichomes to which the mold ''

Rhizopus oligosporus ''Rhizopus oligosporus'' is a fungus of the family Mucoraceae and is a widely used starter culture for the production of tempeh at home and industrially. As the mold grows it produces fluffy, white mycelia, binding the beans together to create ...

'' can be found adhering in the wild.

Soybeans The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean, which has numerous uses. Traditional unfermented food uses of soybeans include soy milk, from which tofu and ...

are pressed into the leaf, and stored. Fermentation occurs resulting in tempeh.

Chemistry

Cyanidin-3-glucoside Chrysanthemin is an anthocyanin. It is the 3-glucoside of cyanidin. Natural occurrences Chrysanthemin can be found in the roselle plant (''Hibiscus sabdariffa'', Malvaceae), different Japanese angiosperms, '' Rhaponticum'' (Asteraceae), The fr ...

is the major

anthocyanin Anthocyanins (), also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical compo ...

found in flowers of ''H. tiliaceus''. Leaves of ''H. tiliaceus'' displayed strong free radical scavenging activity and the highest tyrosinase inhibition activity among 39 tropical plant species in Okinawa. With greater UV radiation in coastal areas, it is possible that leaves and flowers of natural coastal populations of ''H. tiliaceus'' have stronger antioxidant properties than planted inland populations.(Wong ''et al''., 2009; Wong & Chan, 2010).

References

Bibliography

*Masuda, T., Yonemori, S., Oyama, Y., Takeda, Y., Tanaka, T., Andoh, T., Shinohara, A., Nakata, M. (1999). ”Evaluation of the antioxidant activity of environmental plants: activity of the leaf extracts from seashore plants”. ''Journal of Agricultural and Food Chemistry'' 47: 1749–1754. *Masuda, T., Yamashita, D., Takeda, Y., Yonemori, S. (2005). “Screening for tyrosinase inhibitors among extracts of seashore plants and identification of potent inhibitors from ''Garcinia subelliptica''”. ''Bioscience, Biotechnology, and Biochemistry'' 69: 197–201. *Wong, S.K., Lim, Y.Y., Chan, E.W.C. (2009). “Antioxidant properties of ''Hibiscus'': Species variation, altitudinal change, coastal influence and floral colour change”. ''Journal of Tropical Forest Science'' 21(4): 307–315. *Wong, S.K., Chan, E.W.C. (2010). “Antioxidant properties coastal and inland populations of ''Hibiscus tiliaceus''”. ''ISME/GLOMIS Electronic Journal'' 8(1): 1–2. http://www.glomis.com/ej/pdf/EJ_8-1.pdf. {{Taxonbar, from=Q10292396 tiliaceus Flora of Norfolk Island Malvales of Australia Flora of Queensland Flora of the Maldives Trees of Australia Trees of the Philippines Trees of the Pacific Flora of Christmas Island Plants described in 1753 Taxa named by Carl Linnaeus