''Rhodomyrtus tomentosa'' also known as rose myrtle, is a

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the family Myrtaceae, native to southern and southeastern

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

, from

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

, east to southern China,

Hong Kong Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China (abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delta i ...

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...

and the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

, and south to

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

and Sulawesi. It grows in

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 ...

s, natural forest,

riparian zone A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks a ...

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The p ...

s, moist and wet forests, bog margins, from sea level up to 2400 m elevation.

Description

''Rhodomyrtus tomentosa'' is an

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

shrub growing up to 4 m (12 feet) tall. The leaves are opposite, leathery, 5–7 cm long and 2-3.5 cm broad, three-veined from the base, oval, obtuse to sharp pointed at the tip, glossy green above, densely grey or rarely yellowish-hairy beneath, with a wide petiole and an entire margin. 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 are solitary or in clusters of two or three, 2.5–3 cm diameter, with five petals which are tinged white on the outside with purplish-pink or all pink. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is edible, 10–15 mm long, purple, round, three or four-celled, capped with persistent calyx lobes, soft, with 40-45

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s in a double row in each cell; seed dispersal is by frugivorous birds and mammals. Seed production and germination rates are high.Center for Natural Resources, 2003 Synonyms include ''Myrtus canescens'' Lour., ''Myrtus tomentosa'' Aiton, ''Rhodomyrtus parviflora'' Alston, and ''Rhodomyrtus tomentosa'' (Aiton) Wight. Common names include Ceylon hill gooseberry (English), Downy myrtle (English-Florida), Downy rose myrtle (English-Florida), Feijoa (French), Hill gooseberry (English), Hill guava (English), Isenberg bush (English-Hawaii), Myrte-groseille (French), Kemunting (Malaysia), Gangrenzi (China) and Rose myrtle (English-Florida)

Cultivation and uses

It has shown promise as a

fire retardant A fire retardant is a substance that is used to slow down or stop the spread of fire or reduce its intensity. This is commonly accomplished by chemical reactions that reduce the flammability of fuels or delay their combustion. Fire retardants m ...

species for use in

fire break A firebreak or double track (also called a fire line, fuel break, fireroad and firetrail in Australia) is a gap in vegetation or other combustible material that acts as a barrier to slow or stop the progress of a bushfire or wildfire. A firebre ...

s in the

Himalayas The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 10 ...

. It is a popular

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that ...

in gardens in

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

and subtropical areas, grown for its abundant flowers and sweet, edible fruit. The fruit can be made into pies and

jam Jam is a type of fruit preserve. Jam or Jammed may also refer to: Other common meanings * A firearm malfunction * Block signals ** Radio jamming ** Radar jamming and deception ** Mobile phone jammer ** Echolocation jamming Arts and ente ...

s, or used in

salads A salad is a dish consisting of mixed, mostly natural ingredients with at least one raw ingredient. They are typically served at room temperature or chilled, though some can be served warm. Condiments and salad dressings, which exist in a va ...

. In Phú Quốc, Vietnam, the fruits are used to produce a wine called '' rượu sim'', and are also made into jellies, or freshly canned with syrup for export.

Management

It has become an invasive species in some countries, spreading to form large,

monospecific In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

thickets that displace native

flora Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous (ecology), indigenous) native plant, native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' ...

and

fauna Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is ''funga''. Flora, fauna, funga and other forms of life are collectively referred to as ''Biota (ecology ...

. Areas especially affected include

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 ...

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 state ...

, and French Polynesia. It is able to invade a range of habitats, from pine flatwoods to

mangrove A mangrove is a shrub or tree that grows in coastal 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 evolution in severa ...

marshes. It grows in a wide range of

soil Soil, also commonly referred to as earth or dirt Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debri ...

types, including salty coastal soil, but is sensitive to heavy salt spray. It is fire-adapted, meaning it is able to resprout prolifically after fire.Center for Aquatic and Invasive Plants, 2001 This species invades the

understory In forestry and ecology, understory (American English), or understorey (Commonwealth English), also known as underbrush or undergrowth, includes plant life growing beneath the forest canopy without penetrating it to any great extent, but abo ...

of native pinelands in Florida, forming dense monoculture thickets that displace native flora and fauna through overcrowding and competition. Has the potential to alter the natural fire regimes of invaded areas. A risk assessment of ''Rhodomyrtus tomentosa'' for Hawaii and other Pacific islands was prepared by th
Kaulunani Urban Forestry Program
an
US Forest Service
Th

is derived from Pheloung et al. (1999) with minor modifications for use in Pacific islands. The result is a score of 8 and a recommendation of "Likely to cause significant ecological or economic harm in Hawaii and on other Pacific Islands as determined by a high WRA score, which is based on published sources describing species biology and behavior in Hawaii and/or other parts of the world." In integrated management,

seedlings A seedling is a young sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle (embryonic root), the hypocotyl (embryo ...

can be removed manually. Mature shrubs may be felled using a

chainsaw A chainsaw (or chain saw) is a portable gasoline-, electric-, or battery-powered saw that cuts with a set of teeth attached to a rotating chain driven along a guide bar. It is used in activities such as tree felling, limbing, bucking, pru ...

or brush cutter, and the stumps treated with a commercial herbicide.Stocker and Possley 2001 It was introduced to Florida and Hawaii in about 1920 (Degener, 1963 in Langeland and Burks, 1999). In Florida it has now spread to 17 counties (Center for Natural Resources, 2003). On Hawaii it was forming impenetrable thickets on Kauai and Hilo by the 1950s (Hosaka and Thistle, 1954 in Langeland and Burks, 1999). It is currently on th
State of Hawaii noxious weed list
(Meyer, 1998 in PIER, 2003).
/ref> Research was conducted at the University of Florida 1998-2000 to describe the ecology and determine effective control methods for this species. It is also a serious problem on Raiatea, French Polynesia (Meyer, 1998 in PIER, 2003).

Gallery

File:Hoa sim ở Đại Lải.jpg, ''Rhodomyrtus tomentosa'' flowers File:Rhodomyrtus tomentosa immature fruit.JPG, ''Rhodomyrtus tomentosa'' immature fruit. File:Rhodomyrtus tomentosa Bushes Hong Kong.JPG, ''Rhodomyrtus tomentosa'' bushes in

Sai Kung Sai Kung may refer to: * Sai Kung Town, or just Sai Kung, a town and administrative area in the Sai Kung District, Hong Kong * Sai Kung Peninsula, a peninsula in Hong Kong * Sai Kung District, an administrative district in Hong Kong, which does no ...

. File:Rose Myrtle Fruit in Hong Kong.jpg, Up close, and high definition of the native rose myrtle, with a ripe fruit in Hong Kong.

References

{{Taxonbar, from=Q1142869 Myrtaceae Flora of China Flora of Taiwan Flora of tropical Asia