Ochroma is a genus of flowering plants in the mallow family, Malvaceae, containing the sole species Ochroma pyramidale,[1] commonly known as the balsa tree. It is a large, fast-growing tree that can grow up to 30 m tall. Balsa wood is a very lightweight material with many uses. Balsa trees are native to southern Brazil and northern Bolivia, north to southern Mexico.

Ochroma pyramidale Maui
Ochroma pyramidale at the Large Tree Habitat at Tropical Gardens of Maui, Iao Valley Road, Maui, Hawaii, United States
Scientific classification
Kingdom: Plantae
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malvales
Family: Malvaceae
Subfamily: Bombacoideae
Genus: Ochroma
O. pyramidale
Binomial name
Ochroma pyramidale

Bombax pyramidale Cav. ex Lam.
Ochroma bicolor Rowlee
Ochroma concolor Rowlee
Ochroma lagopus Sw.
Ochroma obtusum Rowlee


A member of the mallow family, O. pyramidale is native from southern Mexico to southern Brazil, but can now be found in many other countries (Papua New Guinea, Indonesia, Thailand, Solomon Islands). It is a pioneer plant, which establishes itself in clearings in forests, either man-made or where trees have fallen, or in abandoned agricultural fields. It grows extremely rapidly, up to 27 m in 10–15 years. The speed of growth accounts for the lightness of the wood, which has a lower density than cork. Trees generally do not live beyond 30 to 40 years.[3]

Flowers are produced from the third year onwards, typically at the end of the rainy season when few other trees are in flower. The large flowers open in the late afternoon and remain open overnight. Each may contain a pool of nectar up to 2.5 cm deep. Daytime pollinators include capuchin monkeys. However, most pollination occurs at night. The main pollinators were once thought to be bats, but recent evidence suggests that two nocturnal arboreal mammals, the kinkajou and the olingo, may be the primary pollinators.[3]


Ecuador supplies 95% or more of commercial balsa. In recent years, about 60% of the balsa has been plantation-grown in densely packed patches of around 1000 trees per hectare (compared to about two to three per hectare in nature). It is evergreen or dry-season deciduous, with large 30- to 40-cm, weakly palmately lobed leaves. Being a deciduous angiosperm, balsa is classified as a hardwood despite the wood itself being very soft. It is the softest commercial hardwood. The trees are harvested after six to 10 years of growth. The name balsa comes from the Spanish word for "raft".[4]


Balsa lumber is very soft and light, with a coarse, open grain. The density of dry balsa wood ranges from 40–340 kg/m3, with a typical density around 160 kg/m3.[5] The wood of the living tree has large cells that are filled with water. This gives the wood a spongy texture. It also makes the wood of the living tree not much lighter than water and barely able to float. For commercial production, the wood is kiln-dried for about two weeks, leaving the cells hollow and empty. The large volume-to-surface ratio of the resulting thin-walled, empty cells gives the dried wood a large strength-to-weight ratio because the cells are mostly air. Unlike naturally rotted wood, which soon disintegrates in the rainforests where balsa trees grow, the cell walls of kiln-seasoned balsa wood retain their strong structure of cellulose and lignin.[6]

Because it is low in density but high in strength, balsa is a very popular material for light, stiff structures in model bridge tests, model buildings, and construction of model aircraft; all grades are usable for airworthy control line and radio-controlled aircraft varieties of the aeromodeling sports, with the lightest "contest grades" especially valuable for free-flight model aircraft. However, it also is valued as a component of full-sized light wooden aeroplanes, most notably the World War II de Havilland Mosquito.[6]

Balsa is used to make wooden crankbaits for fishing, especially Rapala lures.

Sticks of dried balsa are useful as makeshift pens for calligraphy when commercial metal nibs of the desired width are not available.

Balsa wood is often used as a core material in composites; for example, the blades of many wind turbines are partly of balsa. In table tennis bats, a balsa layer is typically sandwiched between two pieces of thin plywood made from other species of wood. Balsa wood is also used in laminates together with glass-reinforced plastic (fiberglass) for making high-quality balsa surfboards and for the decks and topsides of many types of boats, especially pleasure craft less than 30 m in length. On a boat, the balsa core is usually end-grain balsa, which is much more resistant to compression than if the soft balsa wood were laid lengthwise.

Balsa is also used in the manufacture of "breakaway" wooden props such as tables and chairs that are designed to be broken as part of theatre, movie, and television productions.

The fifth and sixth generations of the Chevrolet Corvette had floor pans composed of balsa sandwiched between sheets of carbon fiber reinforced plastic.[6]

Norwegian scientist and adventurer Thor Heyerdahl, convinced that early contact between the peoples of South America and Polynesia was possible, built the raft Kon Tiki from balsa logs, and upon it his crew and he sailed the Pacific Ocean from Peru to the Polynesian Tuamotu Archipelago in 1947. However, the Kon Tiki logs were not seasoned and owed much of their (rather slight) buoyancy to the fact that their sap was of lower density than seawater. This serendipitously may have saved the expedition, because it prevented the seawater from waterlogging the wood and sinking the raft.[7]

Balsa wood is also a popular wood type used in the arts of whittling,[6] and surfing. When picture frames still used wood, balsa was often used in a baroque style because of the ease of shaping the design.


Ochroma pyramidalis MS 3425

Balsa on Bota Hill, Limbe Botanical Garden, Cameroon

Ochroma pyramidale1FrancesWHorne

Painting by Frances W. Horne from the Flora Borinqueña

Ochroma pyramidale Maui

Ochroma pyramidale at Tropical Gardens of Maui Iao Valley Rd, Maui

Balsas and kayak

Two balsa rafts and a kayak at Lagos de Montebello in Chiapas, Mexico


Three different sizes of balsa wood stock

Balsa airframe

Balsa construction in a Paul K. Guillow, Inc. "stick and tissue" free-flight rubber scale model airplane.

See also


  1. ^ a b "Search results for Ochroma". The Plant List. Retrieved 1 March 2016.
  2. ^ "Ochroma pyramidale". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 26 October 2009.
  3. ^ a b Angier, N. & Ziegler, C. (2011). "Treetop happy hour". National Geographic. 219 (5): 130–143.
  4. ^ "balsa, n.". OED Online. March 2013. Oxford University Press. 9 May 2013 <http://www.oed.com/view/Entry/15041?redirectedFrom=Balsa&>.
  5. ^ Terry Porter: "Wood Identification and Use", page 160. Guild of Master Craftsman Publications Ltd. 2004
  6. ^ a b c d "Balsa Wood description". Archived from the original on November 22, 2010. Retrieved 2011-01-02.
  7. ^ Thor Heyerdahl (24 December 2013). Kon-Tiki: Across the Pacific by Raft. Skyhorse Publishing Company, Incorporated. ISBN 978-1-62914-634-8.

External links

Alaena amazoula

Alaena amazoula, the yellow Zulu, is a butterfly of the family Lycaenidae. It is found in southern Africa.

The wingspan is 22–28 mm for males and 25–32 mm for females. Adults are on wing from October to May (with a peak from December to January). There is one generation per year.The larvae feed on Cyanobacteria species.

Balsa (disambiguation)

Balsa is the tree Ochroma pyramidale or the light-weight wood it produces

Balsa may also refer to:

Balsa (software), a free and open-source e-mail client for Linux

Balsa (moth), a genus of moths in the Noctuidae family

Balsa (Roman town), in present-day southern Portugal

Balsa (ship), South American boat made of reeds

Balsa, Hungary, village in Szabolcs-Szatmár-Bereg County, Hungary

Balșa (Hungarian: Balsa), a commune in Hunedoara County, Romania

Balsa, a fictional character in the anime and manga Moribito series

Balša I (fl. 1362), ruler of the principality of Zeta in what is now southern Montenegro and northern Albania and founder of the Balšić noble family

Balša II (died 1385), son and successor of Balša I

Balša III (1387–1421), last ruler of Zeta in the Balšić noble family

Walsa, hispanicized spelling Balsa, a mountain in Peru


Bombacaceae were long recognised as a family of flowering plants or Angiospermae. The family name was based on the type genus Bombax. As is true for many botanical names, circumscription and status of the taxon has varied with taxonomic point of view, and currently the preference is to transfer most of the erstwhile family Bombacaceae to the subfamily Bombacoideae within the family Malvaceae in the order Malvales. The rest of the family were transferred to other taxa, notably the new family Durionaceae. Irrespective of current taxonomic status, many of the species originally included in the Bombacaceae are of considerable ecological, historical, horticultural, and economic importance, such as balsa, kapok, baobab and durian.


Bombacoideae is a subfamily of the mallow family, Malvaceae. It contains herbaceous and woody plants. Their leaves are alternate, commonly palmately lobed, with small and caducous stipules. Flowers are hermaphroditic and actinomorphic; the calyx has 5 sepals united at the base, accompanied frequently by an epicalyx (involucel). The corolla has 5 free petals and an androecium of numerous stamens, typically with filaments fused in a staminal tube (column) that surrounds the styles. The pollen is smooth and the ovary superior and pluricarpellate. Fruits are schizocarpous or capsular.


Bombax is a genus of mainly tropical trees in the mallow family. They are native to western Africa, the Indian subcontinent, Southeast Asia, and the subtropical regions of East Asia and northern Australia. It is distinguished from the genus Ceiba, which has whiter flowers.

Common names for the genus include silk cotton tree, simal, red cotton tree, kapok, and simply bombax. Currently four species are recognised, although many plants have been placed in the genus that were later moved.The genus is best known for the species Bombax ceiba, which is widely cultivated throughout tropical and sub-tropical regions of the world. It is native to southern and eastern Asia and northern Australia.

Bombax species are used as food plants by the larvae of some Lepidoptera species including the leaf-miner Bucculatrix crateracma which feeds exclusively on Bombax ceiba.

The tree appears on the flag of Equatorial Guinea.


Dichelopa is a genus of moths belonging to the subfamily Tortricinae of the family Tortricidae.

Dichelopa ochroma

Dichelopa ochroma is a species of moth of the family Tortricidae. It is found on the Marquesas Archipelago in French Polynesia.

Diuris ochroma

Diuris ochroma, commonly known as pale goat orchid, or pale golden moths is a species of orchid that is endemic to south-eastern continental Australia. It has three or four leaves at its base and up to four slightly drooping pale yellow flowers with dark reddish purple streaks. It is an uncommon species found in two disjunct populations, in higher parts of each of New South Wales and Victoria.

Homona phanaea

Homona phanaea is a species of moth of the family Tortricidae. It is found on the Solomon Islands, in New Guinea, on the St. Aignan Islands, the Kei Islands and possibly the Philippines.The larvae feed on Ochroma pyramidale.

Ichigkat Muja – Cordillera del Condor National Park

The Ichigkat Muja – Cordillera del Condor National Park (Spanish: Parque Nacional Ichigkat muja - Cordillera del Cóndor) is a protected area in Peru located in the region of Amazonas. It protects part of the Eastern Andes forests at the Cordillera del Condor mountain range.

List of butterflies of Botswana

This is a list of butterflies of Botswana. About 252 species are known from Botswana, none of which are endemic.

List of woods

This is a list of woods, in particular those most commonly used in the timber and lumber trade.


The Malvales are an order of flowering plants. As circumscribed by APG II-system, the order includes about 6000 species within 9 families. The order is placed in the eurosids II, which are part of the eudicots.

The plants are mostly shrubs and trees; most of its families have a cosmopolitan distribution in the tropics and subtropics, with limited expansion into temperate regions. An interesting distribution occurs in Madagascar, where three endemic families of Malvales (Sphaerosepalaceae, Sarcolaenaceae and Diegodendraceae) occur.

Many species of Malvaceae sensu lato are known for their wood, with that of Ochroma (balsa) being known for its lightness, and that of Tilia (lime, linden, or basswood) as a popular wood for carving. Fruit of the cacao tree (Theobroma cacao) are used as an ingredient for chocolate. Kola nuts (genus Cola) are notable for their high content of caffeine and, in past, were commonly used for preparing of various cola drinks. Other well-known members of Malvales in the APG II sense are daphnes, hibiscus, hollyhocks, okra, baobab trees, cotton, and kapok.

Melaleuca ochroma

Melaleuca ochroma is a plant in the myrtle family, Myrtaceae, and is endemic to the south-west of Western Australia. It is very similar to Melaleuca subfalcata, varying mainly in the length of its stamens and styles. Like M. subfalcata, it has pink to mauve flowers and leaves that are very hairy when young but become glabrous when mature.


Myrmecophytes (mər′mek•ə‚fīt; literally "ant-plant") are plants that live in a mutualistic association with a colony of ants. There are over 100 different genera of myrmecophytes. These plants possess structural adaptations that provide ants with food and/or shelter. These specialized structures include domatia, food bodies, and extrafloral nectaries. In exchange for food and shelter, ants aid the myrmecophyte in pollination, seed dispersal, gathering of essential nutrients, and/or defense. Specifically, domatia adapted to ants may be called myrmecodomatia.

Polypoetes nubilosa

Polypoetes nubilosa is a moth of the family Notodontidae. It is endemic to mid-elevations along the western slope of the Ecuadorian Andes.

The larvae feed on Ochroma pyramidale.


Pyramidale may refer to:

Ellobium pyramidale a species of small, air-breathing, saltmarsh snail, a terrestrial pulmonate gastropod mollusk in the family Ellobiidae

Ochroma pyramidale, commonly known as the balsa tree

Triquetral bone, also known by the Latin term os pyramidale


Satipoella is a genus of beetles in the family Cerambycidae, containing the following species:

Satipoella bufo (Thomson, 1868)

Satipoella heilipoides Lane, 1964

Satipoella ochroma Julio, 2003

Satipoella ochroma

Satipoella ochroma is a species of beetle in the family Cerambycidae. It was described by Julio in 2003.

Taxon identifiers
Ochroma pyramidale
Bombax pyramidale


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