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

flowering Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

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, e.g., including only woody plants with secondary growth, only ...

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 Theobroma cacao, cacao, Cola (plant), cola, cotton, okra, Hibiscus sabdariffa, ...

, with a

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

distribution along coastlines. It has also been introduced to

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

and

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

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

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

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 people, sometimes referred to as Austronesian-speaking peoples, are a large group of peoples who have settled in Taiwan, maritime Southeast Asia, parts of mainland Southeast Asia, Micronesia, coastal New Guinea, Island Melan ...

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'' ( Sundanese & Javanese), ''varo'' ( Malagasy), ''baru'' or ''bebaru'' ( Malay), ''pagu'' ( Chamorro), ''hau'' ( Hawaiian), ''fau'' ( Samoan), ''purau'' ( Tahitian), and vau tree (

Vietnamese Vietnamese may refer to: * Something of, from, or related to Vietnam, a country in Southeast Asia * Vietnamese people, or Kinh people, a Southeast Asian ethnic group native to Vietnam ** Overseas Vietnamese, Vietnamese people living outside Vietna ...

). The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

, ''"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 Great Bri ...

'' species.

Description

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

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

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''.

Distribution and habitat

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

Old World The "Old World" () is a term for Afro-Eurasia coined by Europeans after 1493, when they became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia in the Eastern Hemisphere, previously ...

and

Oceania Oceania ( , ) is a region, geographical region including Australasia, Melanesia, Micronesia, and Polynesia. Outside of the English-speaking world, Oceania is generally considered a continent, while Mainland Australia is regarded as its co ...

, it is a common

coast A coast (coastline, shoreline, seashore) is the land next to the sea or the line that forms the boundary between the land and the ocean or a lake. Coasts are influenced by the topography of the surrounding landscape and by aquatic erosion, su ...

al plant in most of tropical

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

South Asia South Asia is the southern Subregion#Asia, subregion of Asia that is defined in both geographical and Ethnicity, ethnic-Culture, cultural terms. South Asia, with a population of 2.04 billion, contains a quarter (25%) of the world's populatio ...

(including the

Maldives The Maldives, officially the Republic of Maldives, and historically known as the Maldive Islands, is an Archipelagic state, archipelagic country in South Asia located in the Indian Ocean. The Maldives is southwest of Sri Lanka and India, abou ...

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

, parts of

East Asia East Asia is a geocultural region of Asia. It includes China, Japan, Mongolia, North Korea, South Korea, and Taiwan, plus two special administrative regions of China, Hong Kong and Macau. The economies of Economy of China, China, Economy of Ja ...

(as far north as central

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

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

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, and much of the

Pacific Islands The Pacific islands are a group of islands in the Pacific Ocean. They 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 several ...

, including

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

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

New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...

, including

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

Central America Central America is a subregion of North America. Its political boundaries are defined as bordering Mexico to the north, Colombia to the southeast, the Caribbean to the east, and the Pacific Ocean to the southwest. Central America is usually ...

, the

Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America ...

, and much of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. 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 ( , ) is a subregion of Oceania, made up of more than 1,000 islands scattered over the central and southern Pacific Ocean. The indigenous people who inhabit the islands of Polynesia are called Polynesians. They have many things in ...

ns. It is considered native by

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

, 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 (geology), rock, such as sand, gravel, shingle beach, shingle, pebbles, etc., or biological s ...

es, by

rivers A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it ru ...

and in

mangrove A mangrove is a shrub or tree that grows mainly in coastal saline water, saline or brackish water. Mangroves grow in an equatorial climate, typically along coastlines and tidal rivers. They have particular adaptations to take in extra oxygen a ...

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 In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as r ...

and waterlogging and can grow in

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tet ...

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

coral sand Coral sand is a form of aragonite sand particles originating in tropical and sub-tropical marine environments primarily from bioerosion of limestone skeletal material of marine organisms. Often, this is due to corallivores, such as parrotfish ...

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

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

, 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 An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...

ic to

alkali In chemistry, an alkali (; from the Arabic word , ) is a basic 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 soluble base has a pH greater than 7.0. The a ...

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

s ( pH of 5–8.5). Cotton Tree, Queensland, Australia is named for the plant.

Subspecies and varieties

Four subspecies and varieties are accepted. *''Hibiscus tiliaceus'' subsp. ''crestaensis'' – Philippines *''Hibiscus tiliaceus'' subsp. ''pernambucensis'' (synonym ''Hibiscus pernambucensis'' ) – tropical Americas, from Mexico through Central America and the Caribbean to Ecuador and southern Brazil.''Hibiscus tiliaceus'' subsp. ''pernambucensis'' (Arruda) A.Cast.
''

''. Retrieved 24 June 2024. *''Hibiscus tiliaceus'' var. ''potteri'' – Hawaiian Islands *''Hibiscus tiliaceus'' subsp. ''tiliaceus'' – west and west-central tropical Africa, east tropical Africa from Kenya to South Africa, Indian subcontinent, Indochina, southern China, Taiwan, Japan,

Malesia Malesia is a biogeographical region straddling the Equator and the boundaries of the Indomalayan and Australasian realms. It is a phytogeographical floristic region in the Paleotropical kingdom. It was first recognized as a distinct region ...

Papuasia Papuasia is a Level 2 botanical region defined in the World Geographical Scheme for Recording Plant Distributions (WGSRPD). It lies in the southwestern Pacific Ocean, in the Melanesia ecoregion of Oceania and Tropical Asia. It comprises th ...

, northern and eastern Australia, and the tropical Pacific islands.

Uses

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

specific gravity Relative density, also called specific gravity, is a dimensionless quantity defined as the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for solids and liquids is nea ...

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 heavily processed, and is in some sort of firelog, recognizable log or branch form, compared to other forms of wood fuel like pellet fuel, pellets. ...

, and

wood carving Wood carving (or woodcarving) 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 sculpture, ...

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, Plying, plies, fibres, or strands that are plying, twisted or braided together into a larger and stronger form. Ropes have high tensile strength and can be used for dragging and lifting. Rope is thicker and stronger ...

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 or pyrexia in humans is a symptom of an anti-infection defense mechanism that appears with Human body temperature, body temperature exceeding the normal range caused by an increase in the body's temperature Human body temperature#Fever, s ...

s, and its young leafy

shoot Shoot most commonly refers to: * Shoot (botany), an immature plant or portion of a plant * Shooting, the firing of projectile weapons * Photo shoot, a photography session; an event wherein a photographer takes photographs Shoot may also refer t ...

s may be eaten as vegetables.

Native Hawaiians Native Hawaiians (also known as Indigenous Hawaiians, Kānaka Maoli, Aboriginal Hawaiians, or simply Hawaiians; , , , and ) are the Indigenous Polynesian people of the Hawaiian Islands. Hawaiʻi was settled at least 800 years ago by Polynesian ...

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 (watercraft), hull. They can range from small dugout (boat), dugout canoes to large ...

s), ''mouo'' (

fishing net A fishing net or fish net is a net (device), net used for fishing. Fishing nets work by serving as an improvised fish trap, and some are indeed rigged as traps (e.g. #Fyke nets, fyke nets). They are usually wide open when deployed (e.g. by cast ...

floats), and ''au koi'' (

adze An adze () or 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 or carving wood in ha ...

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. Some of the economically important bast fibr ...

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

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

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

bonsai Bonsai (; , ) is the Japanese art of Horticulture, growing and shaping miniature trees in containers, with a long documented history of influences and native Japanese development over a thousand years, and with unique aesthetics, cultural hist ...

. The finest specimens are taken from

Kenting National Park Kenting National Park ( zh, c=墾丁國家公園, hp=Kěndīng Gúojiā Gōngyuán}), commonly known as Kenting ( zh, c=墾丁, hp=Kěndīng), is a national park located on the Hengchun Peninsula of Pingtung County, Taiwan, covering Hengchun, ...

. Lending itself to free

grafting Grafting or graftage is a horticulture, 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 roots ...

, 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 Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

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

tempeh Tempe or tempeh (; , ) 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 oligosporus'' or '' Rhizopu ...

. 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. Soy is a staple crop, the world's most grown legume, and an important animal feed. Soy is a key source of f ...

are pressed into the leaf, and stored. Fermentation occurs resulting in tempeh. Indigenous Australians traditionally used the inner bark of the tree to craft fishing nets and ropes, particularly for use with dugong and turtle harpoons. The wood was also employed in the making of shields. Medicinally, the inner bark and sapwood were soaked in water and heated with hot stones, producing a liquid that was applied to wash wounds. Strips of bark were additionally used as natural bandages, wrapped around injuries to cover and close them.

Chemistry

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

is the major

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

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, from1=Q15768656, from2=Q715899, from3=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 Austronesian agriculture