Rhizophora mucronata Lam.
Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.
- Folk Medicine
- Yields and Economics
- Biotic Factors
The wood (sp. grav. 0.81), durable except in the ground, and difficult to saw,
is used for construction, fish traps, house frames, piling, and poles.
Thousands of tons of mangrove woodchips are exported annually from Indonesia,
Sabah, and Sarawak for pulp and for rayon manufacture (NAS, 1980a). Fruits may
be eaten, after scraping off the outside and boiling with wood ashes, according
to some skeptical accounts (Burkill, 1966). The Wealth of India describes the
fruit as sweet and edible, the juice made into a light wine. Young shoots are
cooked and eaten as a vegetable (C.S.I.R., 19481976). Bark, used for tanning
and dye, may be removed from stems for sale as firewood. Leaves are the source
of a black or chestnut dye (Burkill, 1966). Mangrove extract is used for
maintaining oil-well drilling muds within a desired range of flow (C.S.I.R.,
19481976). Planted along coastal fish ponds to stabilize the banks.
Reported to be astringent, Asiatic mangrove is a folk remedy for angina,
diabetes, diarrhea, dysentery, hematuria, and hemorrhage (Duke and Wain, 1981).
Leaves are poulticed onto armored fish injuries (Watt and Breyer-Brandwijk,
1962).Indochinese use the roots for angina and hemorrhage. Malayans use old
leaves and/or roots for childbirth. Burmese use the bark for bloody urine,
Chinese and Japanese for diarrhea, Indochinese for angina (Perry, 1980).
Wood contains 4.4% resin, 63.4% cellulose (List and Horhammer, 19691979) and
1.5% ash (Watt and Breyer-Brandwijk, 1962). Tannin may vary in dry bark from ca
1350%, leaves contain 9.1%, green fruits 12.0%, and ripe fruits 4.2%. Spent
mangrove bark, after tannin extraction, can be used as a source of furfural
(C.S.I.R., 19481976). Spent bark from North Borneo yields an ash assaying 18%
lime (70% CaCO3).
Honey collected from the flowers is said to be poisonous (C.S.I.R., 19481976).
Evergreen tree 25(30) m high, 70 cm in diameter, with numerous branching
arching stilt roots. Bark brown or blackish, smoothish, with horizontal
fissures. Leaves opposite, elliptical to oblong, 815 cm long, 510 cm wide,
acute, entire, without visible veins, thick and leathery, glabrous,
black-dotted beneath. Petiole 35 cm long. Stipules paired, leaving ring scar.
Flower clusters axillary, 23 times forked, with 38 flowers ca 15 mm long.
Bell-shaped hypanthium with 4 pale yellow, pointed leathery sepals and 4
cream-colored petals 9 mm long. Stamens 8, stalkless, anthers 68 mm long, 4
opposite sepals and 4 opposite petals. Ovary half-inferior, conical, 2-celled,
with 2 ovules in each cell, 2-lobed style. Berry ovoid or conical, 57 cm long,
brown, leathery. Seed 1, viviparous, becoming cigar-shaped, to 40 cm long and 2
cm in diameter (Little, 1983).
Reported from the Africa, Hindustani, Indonesia-Indochina, and China-Japan
Centers of Diversity, Asiatic mangrove, or cvs thereof, is reported to tolerate
diseases, insects, pests, salt, and waterlogging (NAS, 1980a; Little, 1983).
(2n = 36)
Old World tropics from South and East Africa to Madagascar, Seychelles,
Mauritius, southeastern Africa to southern China, Ryukyu throughout Malaysia to
northeastern Australia, Melanesia, and Micronesia. Not widely introduced in
Hawaii (Little, 1983).
Estimated to range from Tropical Moist to Rain through Subtropical Moist to
Rain Forest Life Zones, Asiatic mangrove is estimated to tolerate annual
precipitation of 10 to 80 dm, annual temperature of 20 to 26°C, and pH of
6.0 to 8.5. Hou (1958) suggests that this is the only Malayan mangrove which
can survive complete daily inundation. Little (1983) describes the habitat as
brackish and saline salts of depositing shores and marshes. Of the
Asian species this one is most likely to be found in deep soft mud.
According to the NAS (1980a), planting is usually not needed because natural
regeneration is so successful. In Avicennia and Rhizophora, direct seeding
results in ca 90% survival. Drying the seedlings in the shade a few days before
planting seems to make them much less attractive to crabs, perhaps due to a
buildup of tannin.
In Tamil Nadu, natural regeneration is abundant and plantations for fuel are
managed on 30-year rotations. Clear fellings of Rhizophora may be replaced by
Avicennia (Hou, 1958). Species of Rhizophoraceae, growing only from the tips of
the branches, are often killed by indiscriminate lopping of branches(NAS,
Virgin mangrove stands are reported from Mindanao, where there were 149
trees/ha over 25 cm DBH with 130 m3/ha. Planted forests 40 years old are
projected to yield 400 m3/ha, an average of only 10 m/ha/yr (Hou,
1958). Cannell (1982) cites data on a mangrove forest dominated by Rhizophora,
Ceriops, and Sonneratia, averaging 11 m tall, with an LAI (leaf area index) of
3.74.2. The stemwood and bark on a DM basis weighed 74.4 MT/ha, the prop roots
61.2 MT/ha, the branches 15.8, the foliage 7.4, the fruits 0.3, for a total
standing aerial biomass of 157 MT/ha. The CAI (current annual increment) of
stem wood, bark, and branches was 20 MT/ha/yr, foliage 6.7, fruits 0.3. These
data, taken from a mangrove on Phuket Island, Thailand, regenerated following
clear felling, Suggest annual productivity may attain 20 MT/ha/yr in Asian
Mangrove was the main fuel in the Philippines until World War II (NAS, 1980a).
One great advantage in the eyes of firewood dealers is the ease with which, the
wood is split. With a calorific value higher than oak, it burns with even heat.
Five tons of mangrove firewood is said to equal three tons of Malayan coal, two
tons of Indian or Japanese. It makes an excellent charcoal, rather high in
sulfur (Burkill, 1966). Wood affords good fuel with high calorific value
(4,888 cal, 8,799 Btu) and makes high quality charcoal. In Bangkok, mangrove
charcoal, which burns steadily, giving off intense heat without sparking, sells
for twice the price of other charcoal (NAS, 1980a).
Crabs, great enemies of the seedlings, may damage starting plantations. Browne
(1968) lists the following: Crustacea, Sesarma spp.; Coleoptera,
Poecilus fallax; and Mammalia, Macaca irus.
Complete list of references for Duke, Handbook of Energy Crops
- Browne, F.G. 1968. Pests and diseases of forest plantations trees. Clarendon
- Burkill, J.H. 1966. A dictionary of economic products of the Malay peninsula.
Art Printing Works, Kuala Lumpur. 2 vols.
- Cannell, M.G.R. 1982. World forest biomass and primary production data.
Academic Press, New York.
- C.S.I.R. (Council of Scientific and Industrial Research). 19481976. The wealth
of India. 11 vols. New Delhi.
- Duke, J.A. and Wain, K.K. 1981. Medicinal plants of the world. Computer index
with more than 85,000 entries. 3 vols.
- Hou, D. 1958. Rhizophoraceae. p. 429493. In: van Steenis, C.G.G.J. (ed.),
19551958, Flora Malesiana. series 1, vol. 5, P. Nordhoff Ltd., Republic of
- List, P.H. and Horhammer, L. 19691979. Hager's handbuch der pharmazeutischen
praxis. vols 26. Springer-Verlag, Berlin.
- Little, E.L. Jr. 1983. Common fuelwood crops: a handbook for their
identification. McClain Printing Co., Parsons, WV.
- N.A.S. 1980a. Firewood crops. Shrub and tree species for energy production.
National Academy of Sciences, Washington, DC.
- Perry, L.M. 1980. Medicinal plants of east and southeast Asia. MIT Press,
- Watt, J.M. and Breyer-Brandwijk, M.G. 1962. The medicinal and poisonous plants
of southern and eastern Africa. 2nd ed. E.&S. Livingstone, Ltd., Edinburgh
Last update Friday, January 9, 1998 by aw