Plantation
A plantation is a
large artificially
established forest,
farm or estate,
where crops are
grown for sale,
often in distant
markets rather
than for local on-
site consumption.
The term
plantation is
informal and not
precisely defined.
Crops grown on
plantations include
fast-growing trees
(often conifers),
cotton, coffee,
tobacco, sugar
cane, sisal, some
oil seeds (notably
oil palms) and
rubber trees.
Farms that
produce alfalfa,
Lespedeza, clover,
and other forage
crops are usually
not called
plantations. The
term "plantation"
has usually not
included large
orchards (except
for banana
plantations
), but does include
the planting of
trees for lumber. A
plantation is
always a
monoculture over
a large area and
does not include
extensive
naturally occurring
stands of plants
that have
economic value.
Because of its
large size, a
plantation takes
advantage of
economies of
scale . Protectionist
policies and
natural
comparative
advantage
have contributed
to determining
where plantations
have been located.
Among the earliest
examples of
plantations were
the latifundia of
the Roman Empire,
which produced
large quantities of
wine and olive oil
for export.
Plantation
agriculture grew
rapidly with the
increase in
international trade
and the
development of a
worldwide
economy
that followed the
expansion of
European colonial
empires
. Like every
economic activity,
it has changed
over time. Earlier
forms of
plantation
agriculture were
associated with
large disparities of
wealth and
income, foreign
ownership and
political influence,
and exploitative
social systems
such as indentured
labor and slavery.
The history of the
environmental,
social and
economic issues
relating to
plantation
agriculture are
covered in articles
that focus on
those subjects.
Industrial
plantations are
established to
produce a high
volume of wood in
a short period of
time. Plantations
are grown by
state forestry
authorities (for
example, the
Forestry
Commission
in Britain) and/or
the paper and
wood industries
and other private
landowners (such
as Weyerhaeuser
and International
Paper
in the United
States, Asia Pulp &
Paper (APP) in
Indonesia).
Christmas trees
are often grown
on plantations as
well. In southern
and southeastern
Asia, rubber, oil
palm, and more
recently teak
plantations have
replaced the
natural forest.
Industrial
plantations are
actively managed
for the commercial
production of
forest products.
Industrial
plantations are
usually large-scale.
Individual blocks
are usually even-
aged and often
consist of just one
or two species.
These species can
be exotic or
indigenous. The
plants used for
the plantation are
often genetically
improved for
desired traits such
as growth and
resistance to
pests and
diseases in
general and
specific traits, for
example in the
case of timber
species, volumic
wood production
and stem
straightness.
Forest genetic
resources
are the basis for
genetic
improvement.
Selected
individuals grown
in seed orchards
are a good source
for seeds to
develop adequate
planting material.
Wood production
on a tree
plantation is
generally higher
than that of
natural forests.
While forests
managed for wood
production
commonly yield
between 1 and 3
cubic meters per
hectare per year,
plantations of
fast-growing
species commonly
yield between 20
and 30 cubic
meters or more per
hectare annually; a
Grand Fir
plantation at
Craigvinean in
Scotland has a
growth rate of 34
cubic meters per
hectare per year
(Aldhous & Low
1974), and
Monterey Pine
plantations in
southern Australia
can yield up to 40
cubic meters per
hectare per year
(Everard & Fourt
1974). In 2000,
while plantations
accounted for 5%
of global forest, it
is estimated that
they supplied
about 35% of the
world's roundwood
[1].
Growth cycle
In the first
year, the
ground is
prepared
usually by the
combination of
burning,
herbicide
spraying, and/
or cultivation
and then
saplings are
planted by
human crew or
by machine.
The saplings
are usually
obtained in
bulk from
industrial
nurseries,
which may
specialize in
selective
breeding in
order to
produce fast
growing
disease- and
pest-resistant
strains.
In the first few
years until the
canopy closes,
the saplings
are looked
after, and may
be dusted or
sprayed with
fertilizers or
pesticides until
established.
After the
canopy closes,
with the tree
crowns
touching each
other, the
plantation is
becoming
dense and
crowded, and
tree growth is
slowing due to
competition.
This stage is
termed 'pole
stage'. When
competition
becomes too
intense (for
pine trees,
when the live
crown is less
than a third of
the tree's total
height), it is
time to thin out
the section.
There are
several
methods for
thinning, but
where
topography
permits, the
most popular is
'row-thinning',
where every
third or fourth
or fifth row of
trees is
removed,
usually with a
harvester.
Many trees are
removed,
leaving regular
clear lanes
through the
section so that
the remaining
trees have
room to expand
again. The
removed trees
are delimbed,
forwarded to
the forest road,
loaded onto
trucks, and
sent to a mill. A
typical pole
stage
plantation tree
is 7 –30 cm in
diameter at
breast height
(dbh). Such
trees are
sometimes not
suitable for
timber, but are
used as pulp
for paper and
particleboard,
and as chips for
oriented strand
board
.
As the trees
grow and
become dense
and crowded
again, the
thinning
process is
repeated.
Depending on
growth rate
and species,
trees at this
age may be
large enough
for timber
milling; if not,
they are again
used as pulp
and chips.
Around year
10-60 the
plantation is
now mature
and (in
economic
terms) is falling
off the back
side of its
growth curve.
That is to say,
it is passing the
point of
maximum wood
growth per
hectare per
year, and so is
ready for the
final harvest.
All remaining
trees are felled,
delimbed, and
taken to be
processed.
The ground is
cleared, and
the cycle is
repeated.
Some plantation
trees, such as
pines and
eucalyptus, can be
at high risk of fire
damage because
their leaf oils and
resins are
flammable to the
point of a tree
being explosive
under some
conditions.
Conversely, an
afflicted
plantation can in
some cases be
cleared of pest
species cheaply
through the use of
a prescribed burn,
which kills all
lesser plants but
does not
significantly harm
the mature trees.
large artificially
established forest,
farm or estate,
where crops are
grown for sale,
often in distant
markets rather
than for local on-
site consumption.
The term
plantation is
informal and not
precisely defined.
Crops grown on
plantations include
fast-growing trees
(often conifers),
cotton, coffee,
tobacco, sugar
cane, sisal, some
oil seeds (notably
oil palms) and
rubber trees.
Farms that
produce alfalfa,
Lespedeza, clover,
and other forage
crops are usually
not called
plantations. The
term "plantation"
has usually not
included large
orchards (except
for banana
plantations
), but does include
the planting of
trees for lumber. A
plantation is
always a
monoculture over
a large area and
does not include
extensive
naturally occurring
stands of plants
that have
economic value.
Because of its
large size, a
plantation takes
advantage of
economies of
scale . Protectionist
policies and
natural
comparative
advantage
have contributed
to determining
where plantations
have been located.
Among the earliest
examples of
plantations were
the latifundia of
the Roman Empire,
which produced
large quantities of
wine and olive oil
for export.
Plantation
agriculture grew
rapidly with the
increase in
international trade
and the
development of a
worldwide
economy
that followed the
expansion of
European colonial
empires
. Like every
economic activity,
it has changed
over time. Earlier
forms of
plantation
agriculture were
associated with
large disparities of
wealth and
income, foreign
ownership and
political influence,
and exploitative
social systems
such as indentured
labor and slavery.
The history of the
environmental,
social and
economic issues
relating to
plantation
agriculture are
covered in articles
that focus on
those subjects.
Industrial
plantations are
established to
produce a high
volume of wood in
a short period of
time. Plantations
are grown by
state forestry
authorities (for
example, the
Forestry
Commission
in Britain) and/or
the paper and
wood industries
and other private
landowners (such
as Weyerhaeuser
and International
Paper
in the United
States, Asia Pulp &
Paper (APP) in
Indonesia).
Christmas trees
are often grown
on plantations as
well. In southern
and southeastern
Asia, rubber, oil
palm, and more
recently teak
plantations have
replaced the
natural forest.
Industrial
plantations are
actively managed
for the commercial
production of
forest products.
Industrial
plantations are
usually large-scale.
Individual blocks
are usually even-
aged and often
consist of just one
or two species.
These species can
be exotic or
indigenous. The
plants used for
the plantation are
often genetically
improved for
desired traits such
as growth and
resistance to
pests and
diseases in
general and
specific traits, for
example in the
case of timber
species, volumic
wood production
and stem
straightness.
Forest genetic
resources
are the basis for
genetic
improvement.
Selected
individuals grown
in seed orchards
are a good source
for seeds to
develop adequate
planting material.
Wood production
on a tree
plantation is
generally higher
than that of
natural forests.
While forests
managed for wood
production
commonly yield
between 1 and 3
cubic meters per
hectare per year,
plantations of
fast-growing
species commonly
yield between 20
and 30 cubic
meters or more per
hectare annually; a
Grand Fir
plantation at
Craigvinean in
Scotland has a
growth rate of 34
cubic meters per
hectare per year
(Aldhous & Low
1974), and
Monterey Pine
plantations in
southern Australia
can yield up to 40
cubic meters per
hectare per year
(Everard & Fourt
1974). In 2000,
while plantations
accounted for 5%
of global forest, it
is estimated that
they supplied
about 35% of the
world's roundwood
[1].
Growth cycle
In the first
year, the
ground is
prepared
usually by the
combination of
burning,
herbicide
spraying, and/
or cultivation
and then
saplings are
planted by
human crew or
by machine.
The saplings
are usually
obtained in
bulk from
industrial
nurseries,
which may
specialize in
selective
breeding in
order to
produce fast
growing
disease- and
pest-resistant
strains.
In the first few
years until the
canopy closes,
the saplings
are looked
after, and may
be dusted or
sprayed with
fertilizers or
pesticides until
established.
After the
canopy closes,
with the tree
crowns
touching each
other, the
plantation is
becoming
dense and
crowded, and
tree growth is
slowing due to
competition.
This stage is
termed 'pole
stage'. When
competition
becomes too
intense (for
pine trees,
when the live
crown is less
than a third of
the tree's total
height), it is
time to thin out
the section.
There are
several
methods for
thinning, but
where
topography
permits, the
most popular is
'row-thinning',
where every
third or fourth
or fifth row of
trees is
removed,
usually with a
harvester.
Many trees are
removed,
leaving regular
clear lanes
through the
section so that
the remaining
trees have
room to expand
again. The
removed trees
are delimbed,
forwarded to
the forest road,
loaded onto
trucks, and
sent to a mill. A
typical pole
stage
plantation tree
is 7 –30 cm in
diameter at
breast height
(dbh). Such
trees are
sometimes not
suitable for
timber, but are
used as pulp
for paper and
particleboard,
and as chips for
oriented strand
board
.
As the trees
grow and
become dense
and crowded
again, the
thinning
process is
repeated.
Depending on
growth rate
and species,
trees at this
age may be
large enough
for timber
milling; if not,
they are again
used as pulp
and chips.
Around year
10-60 the
plantation is
now mature
and (in
economic
terms) is falling
off the back
side of its
growth curve.
That is to say,
it is passing the
point of
maximum wood
growth per
hectare per
year, and so is
ready for the
final harvest.
All remaining
trees are felled,
delimbed, and
taken to be
processed.
The ground is
cleared, and
the cycle is
repeated.
Some plantation
trees, such as
pines and
eucalyptus, can be
at high risk of fire
damage because
their leaf oils and
resins are
flammable to the
point of a tree
being explosive
under some
conditions.
Conversely, an
afflicted
plantation can in
some cases be
cleared of pest
species cheaply
through the use of
a prescribed burn,
which kills all
lesser plants but
does not
significantly harm
the mature trees.
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