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147
Bertholletia excelsa
Lecythidaceae
Brazil nut tree Distribution
Bolivia, Brazil (Acre, Amapá, Amazonas,
Maranháo, Mato Grosso, Pará, Rondônia), Colombia, French Guiana,
Guyana, Peru, Suriname, Venezuela
Habitat Tropical,
lowland, moist, non-seasonal, closed forest. Trees grow best on deep well-drained
alluvial soils on high ground not subject to flooding
(Prance & Mori, 1979). Population
Status and Trends A widely
occurring emergent of Amazonian forest, the Brazil nut tree has experienced major
declines in its population because of deforestation.
One of the greatest concentrations of stands exists in Tocantins valley where
various activities, from the construction of the Transamazon
railway to the building of a reservoir, have brought about a shrinking in the
gene pool (Smith et al.,
1992). An area of 200,000ha
in south Pará has been purchased by the government with the aim of settling
landless farmers (Salamâo, 1991). There are also plans
to establish a pig-iron smelter along the Carajás-Itaqui railway which is
likely to result in the clearance of vast areas of forest to supply
carbon (Smith et
al., 1992). Trees remaining in the vast cattle
ranches of Pará and Acre are neglected and dying (Clement, 1991). However,
large natural stands still exist in northern
Bolivia (Killeen, 1997). The species is locally abundant in Suriname, where Amerindians
harvest the seeds (Werkhoven,
1997). Almost all Brazil nuts consumed around the world come from wild trees (Smith
et al.,
1992). Little is known about
the impact of seed gathering on regeneration, but it clearly can be limited under
certain exploitative regimes. Agoutis provide a vital function
not only of dispersing the seed but of opening the pod, which if left closed generally
imprisons the seeds until they rot. As part of some
regimes agoutis may be hunted or driven away because of lack of food sources as
a result of overextraction of Brazil nuts (Broekhoven,
1993). The sustainable harvesting of nuts by indigenous people in extractive forest
reserves offers the most promising protection
for remaining natural stands (Wickens, 1995). Role
of species in the Ecosystem The
seeds are encased in large pods of 0.5-0.75kg weight. The seeds are eaten by brocket
deer (Mazama americana),
the nocturnal paca (Agouti
paca), other agoutis (Dasyprocta
spp.) and squirrels. Agoutis and squirrels aid dispersal by caching the seeds.
Macaws commonly damage the
seeds and seed capsule before they have matured. The seeds have also played a
significant role in the diets of numerous indigenous
peoples. Flowers are pollinated by euglossine, anthophorid and apine bees
in the genera Xylocopa, Bombus,
Centris, Epicharis
and Eulaema (Smith
et al.,
1992). Threats
Logging of the habitat, burning, increasing
settlement and agriculture, infrastructural and industrial development (Pires
OBrien, 1996). Utilisation
The seed provides a highly nutritious food,
high in protein and unsaturated fatty acids. Seed oil can be used in cooking and
soap-making, and the seed capsule
is useful as a fuel or for craft-making (Wickens, 1995). The timber is excellent
but living trees are considered more valuable
as a source of nuts. It is used in the construction of ships, water tanks and
railway ties but is not thought to have commercial value in
the international market (Flynn, 1994). The bark is used for caulking ships (FAO,
1986). Trade
Production of Brazil nuts for export is concentrated
in north-west Amazonia and Acre in Brazil and the Pando/Beni region in Bolivia
(Wickens, 1995). Pará is also a major
area of production (Smith et al., 1992). At one time Brazil nuts were second only
to rubber as an export crop
from Amazonian Brazil (Wickens, 1995). Annual nut production decreased from 104,000
tonnes in 1970 to 50,000 tonnes in 1980
because of habitat loss (Mori et al.,
1990). It continues to decrease at an average rate of 820 tonnes pa (Wickens,
1995). U.S.A, U.K. and Germany
are the major importers (Wickens, 1995). World
Production of Brazil nuts (1000 tons) Year
Brazil Bolivia
Peru Total
Approx. price FOB
£/ton
or US$/lb 1970 50
- - 50
£378 1971 30
- - 30
£487 1972 65
- - 65
£466 1973 65
- - 65
$0.63 1974 33
- - 33
$0.77 1975 50
- - 50
$0.59 1976 32
- - 32
$0.76 1977 38
- - 38
$1.28 1978 32
8 2 42
$1.33 1979 50
7 3 60
$1.04 1980 60
- - 60
$0.98 1981 40
- - 40
$1.07 1982 28
- - 28
$1.63 1983 35
- - 35
$1.41 1984 35
10 6 51
$0.81 1985 40
6 4 50
$0.82 1986 35
8 5 48
$0.90 1987 33
10 7 50
$1.09 1988 29
7 5 41
$1.18 1989 25
9 6.5 40.5
$1.70 1990 42
9 3 54
$1.48 1991 24
5.5 2.5 32
$1.36 Average
36.3 8.0
4.4 45.2
$1.20 Source:
La Fleur 1992 in Wickens, 1995 IUCN
Conservation category VU A1acd+2cd
according to the Americas Regional Workshop for the WCMC/SSC Conservation
and sustainable
management of
trees project
(WCMC, 1996). Conservation
Measures It is illegal to
fell trees in Brazil (Pires OBrien, 1996). However, felling continues, particularly
in southern Pará and northern Mato Grosso (Smith
et al.,
1992). Populations exist in various large protected areas and in places which
are safe from logging and habitat clearance, such as
corporate property, Companhia Vale do Rio Doce. A research programme on Brazil
nut population biology and ecology is set up in north-east
Bolivia by the University of Beni in Riberalta (IIFA), Utrecht University and
the Netherlands Committee for IUCN. Forest
Management and Silviculture Natural
regeneration is rare in some areas. Trees can sprout from root systems of fallen
trees. It is believed that many Brazil nut groves have been
planted by indigenous people since the time when hunter gathers first colonised
the rainforest (Smith et al., 1992). The pollinators dependence
on the availability of a variety of forest plants, including orchid species, as
a source of food and chemical signals important in reproduction,
has been thought to limit the establishment of plantations outside the rainforest.
However, it is possible to obtain sizeable harvests
from plantation sources given appropriate soil conditions and a well-defined dry
season (Smith et al.,
1992). Trees are 12-16 years old
before fruiting, with maximum production at 25-30 years. Cultivated compact grafted
trees may start production after 8 years. During a good
year 100-120kg of unshelled seeds may be harvested from a single tree (Wickens,
1995). The Agricultural Research Centre of the Humid
Tropics (CPATU-EMBRAPA) in Brazil are in the process of creating a clonal germplasm
collection and providing clones for commercial
plantations (Wickens, 1995). The species has been introduced to Malaysia, Sri
Lanka, Java, Hawaii and the Caribbean (Wickens,
1995). References
Broekhoven, G. 1996. Non-timber
forest products:
ecological and
economic aspects
of exploitation
in Colombia,
Ecuador and
Bolivia. IUCN,
Gland, Switzerland. Chudnoff,
M. 1984. Tropical timbers
of the
world. Forest Products Laboratory Madison, Wisconsin:
United States Department of Agriculture.
464pp. Clement, C.R. 1991.
Amazonian fruits: a neglected and threatened, but potentially rich resource. Diversity
Magazine, 7, 56-59. FAO
Forestry Department. 1986. Databook
on endangered
tree and
shrub species
and their
provenances. Rome: FAO. 524pp. Flynn,
J.H. 1994. A guide
to useful
woods of
the world.
King Philip Publishing Co., Maine, U.S.A. 382pp. Harcourt,
C.S. & J.A. Sayer (eds.). 1996. The
conservation atlas
of tropical
forests: the
Americas. Simon & Schuster, Singapore.
IBAMA. 1992. Lista
oficial de
espécies da
flora Brasileira
ameaçadas de
extinçao. (unpublished). 4pp.
Killeen, T. 1997. Comments on the species
summaries for Bolivia. Killeen,
T.J., E. Garcia & S.G. Beck (eds.). 1993. Guia
de arboles
de Bolivia.
Missouri Botanical Garden, Missouri. 958pp. La
Fleur, J.R. 1991 Marketing of
Brazil nuts.
FAO, Rome. Mori, S. A., G.T.
Prance, & C. Zeeuw. 1990. Lecythidaceae - Part II: The zygomorphic-flowered
New World genera (Couroupita, Corythophora,
Bertholletia, Couratari,
Eschweilera, &
Lecythis).
Flora Neotropica, Monograph
21 (II).
376pp.
Newton, A.C. 1996. The sustainability of
uses of trees. Unpublished report for the WCMC/SSC Conservation
and sustainable
management of
trees project.
Prance, G.T. & S.A. Mori. 1979. Lecythidaceae
Part I: The actinomorphic-flowered New World Lecythidaceae (Asteranthus,
Gustavia, Grias,
Allantoma and
Cariniana).
Flora Neotropica Monograph
21 (I).
270pp.
Pires OBrien, J. 1996. Completed data
collection forms for Brazilian Lecythidaceae. Roosmalen,
M.G.M. van. 1985. Fruits of the Guianan flora. Wageningen: Institute of Systematic
Botany, Utrecht and Silvicultural Dept of Wageningen
Agricultural University. Salamâo,
R.P. 1991. Estrutura e densidade de Bertholletia excelsa H.&B. (castanheira)
nas regiôes de Carajás e Marabá, Estado do Pará.
Belém, Bol. Mus. Para. Emilio Goeldi,
sér. Bot. 7(1): 47-68. WCMC.
1996. Report of the Second Regional Workshop, held at CATIE, Turrialba, Costa
Rica, 18-20 November 1996. Conservation
and sustainable
management of trees project.
(unpublished).
Wickens, G.E. 1995. Edible nuts. Non-wood
Forest Products 5. Food and Agriculture Organization of the United Nations. 197
pp. Werkhoven, M.C.M. 1997.
Threatened trees of Suriname. A list compiled for the WCMC/SSC Conservation
and sustainable
management of
trees project.