Balsam apple

This article deals with the tropical tree. An overview of other meanings of the word "balsam apple" can be found under balsam apple (disambiguation) .

Balsam apple
Balsam apple ( Clusia rosea ) on Maui ( Hawaii )
Systematics
Rosids Eurosiden II Order : Malpighiales (Malpighiales) Family : Clusiaceae Genre : Clusia Type : Balsam apple
Scientific name
Clusia rosea
Jacq.

The balsam apple ( Clusia rosea Jacq. ), And balsam pear , Rose Clusie , autographs tree , Cupey or Copey called, is a tropical tree from the Caribbean . The fruits of the tree, reminiscent of apples , are inedible.

description

View of the trunk

Epiphytic growth of seedlings on a eucalyptus tree

The evergreen , hemi- epiphytic and fast-growing tree can grow up to a maximum of 15 to 20 meters high, but mostly remains smaller in its dimensions (by 10 meters). It forms a broad and dense, sometimes widely spreading crown. The trunk is relatively short, with a trunk diameter (BHD) of up to 60 centimeters. The soil rooting is shallow, buttress roots are not formed and neither are tap roots . The bark is gray-brownish in color and relatively smooth with isolated wart-like bulges. If the bark is injured, a yellowish milky juice escapes . This milky sap (botanically incorrect “ balsam ”) is also produced by other parts of the plant (leaves, fruits) and used to be used, among other things, to seal boats. Hence the English term "pitch apple"; in German " Pechapfel ".

A characteristic feature are the aerial roots found on the trunk and branches , which often hang down like cords (diameter 6 to 8 mm) and are mainly formed by free-standing trees. Once they reach the ground, the aerial roots rapidly increase in diameter and can develop into columnar secondary trunks. Seedlings that grow epiphytically on the forks of the mother tree or other trees first form aerial roots and after reaching the ground quickly grow in width, where they can wrap the host tree with their roots and bring it to death, which, however, rarely happens. This growth, reminiscent of strangler figs , is said to have led to the common English name scotch attorney ("Scottish lawyer").

With regard to the location, Clusea rosea is relatively undemanding. It grows on sandy and clayey soils as well as on soils of variable acidity ( pH 5.0 to 8.0). The tree is a light tree species and moderately shade-tolerant. In its natural range (the Caribbean islands) there are annual mean temperatures of 25.5 to 27 ° C and annual precipitation between 600 and 3000 mm. It survives dry spells of one to two months, but is generally sensitive to frosts and cold winter winds. The tree tolerates salt water spray , which is why it is often planted in Florida close to the coast.

Leaves, flowers and fruits

The paddle-shaped and opposite, leathery and bare leaves of the tree are obovate with a rounded to blunt, sometimes incorrectly heart-shaped tip and they are relatively thick and stiff. The lamina is wedge-shaped into a 1.2 to 2.5 cm long petiole. The leaves are glossy and dark green on the top and mostly light green on the underside. The leaf blade is 7.5 to 15 cm long and 5 to 11 cm wide with a full margin. The middle vein is light green in the lower half.

Fruits and leaves with labels

If the leaf is injured, a clearly visible scar forms for a long time (the leaves have an average lifespan of 15 months). This property has led to the name "autograph tree". At the time of the Spanish colonial rule , soldiers used the sheets of paper they had "written on" as playing cards and note paper. They have also been sent as postcards. In botanical gardens and public parks, the tree is often defaced by people who leave their graffiti .

Clusea rosea is dioecious and dioecious and blooms mostly in the summer months. Armpit or fasting, short zymous inflorescences are formed, with up to three flowers or the flowers appear individually. They are underlaid with front and cover sheets .

The flowers with double inflorescence are very decorative and white or white-pink in color. The flowers are about 7.5 cm wide and consist of four to six green-reddish sepals and usually six to eight overlapping, obovate, approx. 3 cm long petals . There are hermaphroditic, female and male flowers. Female flowers have a small ring of overgrown, short staminodes that secrete a sticky liquid that attracts insects. In addition, there is a usually from six to ten carpels existing, above-permanent ovary with sedentary, multilobe, radiärer scar . Male flowers have numerous, circularly arranged, functional, basal fused stamens in two circles and fused, short staminodes in the middle that secrete a sticky sap.

The greenish-brown, reddish, leathery fruits, with adherent calyx and permanent, radial stigma, are fleshy, spherical, septicidal capsule fruits up to 8 cm in size . The ripe fruit weight is around 70 grams. Only superficially does the fruit resemble an apple. The fruits are not edible and have even been described as poisonous to humans. But they are eaten by bats and birds. When ripe, the fruits open up in a star-shaped, claw-like manner and fall off the tree. When open, six to ten seed compartments are visible, in each of which around 12 seeds are embedded, which are covered with a sticky, reddish aril . The thousand grain mass of the seeds is about 12 grams (1 seed = 0.012 g). The opened fruits attract numerous birds, which further spread the seeds. As the fruit dries, it turns brown and the segments fall apart.

Asexual reproduction ( apomixis ) is also possible.

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  Male flower with the stamens in two circles and in the middle are the staminodes that secrete a sticky sap

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  Female flower with a ring of staminodes around the ovary that secrete a sticky sap

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  Ripe open fruit

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  Fallen open fruit with seed compartments

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  Seeds with a reddish aril

Occurrence

The original distribution area of ​​the tree is the Caribbean ( Cuba , Jamaica , Hispaniola , Puerto Rico , Bahamas etc.) but also North South America to South Mexico. It has also been used in southern Florida for a long time, but was probably only introduced there in earlier centuries. The plant was also exported to other regions of the world. B. to South Africa , India, West Brazil and Sri Lanka . In Hawaii it enjoyed great popularity for a long time and was planted many times. This is now seen more critically and the tree is classified as an invasive plant. Older reports of an occurrence in other South American countries (Mexico, Colombia, Venezuela) are probably based on a confusion with other Clusia species.

Systematics

Graphical comparison of the size of the balsam apple (7) with other tropical plants in the Caribbean, the aerial roots clearly shown

The generic name Clusia refers to the French-Dutch doctor and botanist Charles de l'Écluse ( Carolus Clusius , 1526-1609). The Dutch-Austrian botanist Nikolaus Joseph von Jacquin (1727-1817), who coined the name in his Enumeratio Systematica Plantarum 34 published in 1760, is considered to be the actual first scientific descriptor of the species .

Synonyms are Clusia rosea L. , Clusia retusa Poir. , Clusia silvicola Britton , Elwertia retusa Raf. , Firkea rosea (Jacq.) Raf. , Clusia rosea var. Colombiana Cuatrec. , Clusia rubra cancer , Clusia alba Kunth , Clusia plukenetii Hodge non Urb.

biochemistry

The balsam apple is one of the so-called CAM plants , in which the uptake of carbon dioxide (CO ₂ ) and its further assimilation are temporally separated from each other. During the night, CO _{2 is} absorbed through the open stomata , fixed in the form of malic acid and stored in vacuoles. During the day the stomata are closed, the CO ₂ is released again from the malic acid and used in the Calvin cycle to build up carbohydrates. Ultimately, this separation represents an adaptation to hot, dry climates, as it prevents the evaporation of water via the stomata during the day.

Economic use

The economic use of the tree is limited. Mostly it serves as a purely ornamental tree and, due to its dense tree top, as a privacy screen or shade provider. The fruits and large leaves, which produce a lot of waste, can be disadvantageous. The wood is hard and relatively heavy ( r 15  = 0.74 g / cm ³ ). The core is reddish-brown and the sapwood is a bit lighter. Annual rings are not formed. Despite its hardness, the wood is not very durable, difficult to dry and is not very resistant to termite damage . Insect pests are of less importance for the population than windthrow and trunk breaks as a result of the regularly occurring tropical cyclones in the area of ​​distribution. The wood is used as simple construction and firewood. Due to its relative modesty, the tree is considered to be of considerable importance for preserving forests.

literature

• W. Fawcett, AB Rendle: Flora of Jamaica. Vol. 5, British Museum, 1926, pp. 191 ff, online at biodiversitylibrary.org, accessed on October 25, 2018.
• I. Roth, H. Lindorf: South American Medicinal Plants. Springer, 2002, ISBN 978-3-642-07544-5 , pp. 255 ff.
• Ulrich Lüttge: Clusia: A Woody Neotropical Genus of Remarkable Plasticity and Diversity. Springer, 2007, ISBN 978-3-540-37242-4 .
• Klaus Kubitzki : The Families and Genera of Vascular Plants. Vol. IX, Springer, 2007, ISBN 978-3-540-32214-6 , pp. 48-56.

Web links

Commons : Balsam Apple ( Clusia rosea )  - Collection of images, videos and audio files

• Clusia rosea at Useful Tropical Plants, accessed October 24, 2018.

Individual evidence

1. ^ Wilhelm (William) Ulrich: International dictionary of plant names. Schmidt, 1872, p. 58, archive.org .
2. ↑ ^{a b} Umberto Quattrocchi: CRC World Dictionary of Medicinal and Poisonous Plants. CRC Press, 2012, ISBN 978-1-4822-5064-0 , p. 1029.
3. ↑ ^{a b} Julia F. Morton: Pity the Pitch Apple - treat it as a spreading tree . In: Proc. Fla. State hoard. Soc. tape 101 , 1988, pp. 122–127 (English, PDF ).
4. ↑ ^{a b c d e f g} Peter Schütt, Ulla M. Lang: Clusia rosea . In: Schütt, Weisgerber, Schuck, Lang, Stimm, Roloff (ed.): Trees of the tropics . Nikol Verlagsgesellschaft, Hamburg 2006, ISBN 978-3-933203-79-3 , p. 231-235 .
5. ↑ Rolf Blancke: Color Atlas Plants of the Caribbean and Central America. Ulmer, 1999, ISBN 3-8001-3512-4 , p. 86.
6. ^ Klaus Kubitzki: The Families and Genera of Vascular Plants. P.56.
7. ^ Edward F. Gilman, Dennis G. Watson: Clusia rosea , Pitch-Apple. (PDF) In: Forest Service, Department of Agriculture Fact Sheet ST-172. November 1993, accessed October 14, 2018 . 
8. ^ Edward F. Gilman, Dennis G. Watson: Clusia rosea: Pitch Apple. (PDF) University of Florida, accessed October 14, 2018 . 
9. ^ Klaus Kubitzki: The Families and Genera of Vascular Plants. P. 52.
10. ↑ Michael D. Cheek, Reshnee Lalla: A description of the naturalized Clusia rosea Jacq. (Clusiaceae) populations in South Africa. In: Bothalia. Vol. 47, no. 1, 2017, doi: 10.4102 / abc.v47i1.2229 , (online) , accessed October 25, 2018.
11. ↑ Forest Starr, Kim Starr, Lloyd Loope: Clusia rosea. (PDF) United States Geological Survey - Biological Resources Division Haleakala Field Station, Maui, Hawai'i, January 2003, accessed October 14, 2018 . 
12. ^ Hawaii's Most Invasive Horticultural Plants. Hawaii State Alien Species Coordinator, May 2001, accessed October 14, 2018 . 
13. ↑ Nikolaus Joseph von Jacquin: Enumeratio Systematica Plantarum, quas in insulis Caribaeis vicinaque Americes continente detexit novas, aut iam cognitas emendavit (“Systematic listing of the plants that were newly discovered on the islands of the Caribbean and the adjacent American continent, or improvements to them that were already known ") . Verlag Theodor Haak, Leiden 1760, p. 34 (Latin, online ).