Forestry & Forest Sciences · Silviculture · also Plantation Forestry, Industrial and Energy Plantations, Intensive Forest Management
Growing planted forests for wood, fibre and energy: species choice, intensive establishment and management, productivity, short-rotation coppice and the social and environmental issues of plantations.
In the exams: ICAR AICE-JRF 59 Unit 2 (plantation forestry, industrial and energy plantations); ICAR AIEEA-PG Group 09 (man-made plantations); IFoS Forestry Paper I Section A (plantation silviculture, enhanced productivity)
Plantation forestry is the growing of planted forests, usually of one or a few species, managed intensively for wood, fibre or energy. Planted forests make up a small fraction of the world's forest area but supply a large and rising share of its industrial wood, and their productivity per hectare can be many times that of natural forests. Short-rotation crops, such as eucalypt pulpwood, poplar and willow coppice and energy plantations, push intensity further, with rotations of a few years to about a decade. Plantations can relieve pressure on natural forests, restore degraded land and support rural incomes; they can also replace valuable ecosystems, deplete water, concentrate pest risk and displace people. Understanding both sides is part of the subject.
This manual covers planted forests worldwide and their roles; the choice of species and clones; intensive site preparation, fertilisation and weed control; spacing, rotation and productivity measured as mean annual increment; regimes for pulpwood, sawlogs and veneer; short-rotation coppice and energy plantations; plantation health and the risks of monocultures; the effects of plantations on water, soils and biodiversity; outgrower and contract-farming schemes; and bamboo plantations. It builds on forest nursery and plantation establishment, stand tending and thinning, and silviculture of species, and on forest genetics and tree improvement for improved planting stock; vegetative propagation of clones is covered in forest biotechnology and propagation.
The subject is examined in postgraduate and doctoral entrance and fellowship examinations in forestry (plantation forestry, industrial and energy plantations, man-made plantations), in civil-service forestry examinations (plantation silviculture and enhanced productivity) and in professional forester registration and certification examinations (intensive plantation regimes, plantation health and certification). Productivity, rotation and cost figures vary greatly with species, genetic material, site, climate and management, and are given here as ranges or examples.
FAO's Global Forest Resources Assessment distinguishes naturally regenerating forests from planted forests, established through planting or deliberate seeding. Within planted forests, plantation forests are intensively managed, even-aged stands of one or two species, native or introduced, established mainly for production; other planted forests, such as those planted for restoration or protection, resemble natural forests more closely. According to FRA 2020, planted forests covered about 294 million hectares, roughly 7 per cent of the world's forest area, and plantation forests about 131 million hectares, roughly 3 per cent. Planted forest area has been increasing, especially in East Asia, Europe and North America, while the largest areas of fast-growing plantations of exotic species are in the southern hemisphere, notably Brazil, Chile, Uruguay, South Africa, New Zealand and Australia, and in China and South-East Asia.
Despite their small area, plantations supply a large share of the world's industrial roundwood, commonly estimated at about a third or more, and that share is expected to rise. Some countries, such as New Zealand, Chile and Uruguay, obtain nearly all their industrial wood from plantations. In some densely populated countries of South and East Asia, plantations by public agencies, industries and farmers, together with trees on farms and other land outside forests, supply most of the wood used by industry, while natural forests are largely protected.
Planted forests serve many roles. Industrial plantations supply pulpwood, sawlogs, veneer logs, poles and panels; energy plantations supply fuelwood, charcoal and biomass for power; protective plantations stabilise dunes, slopes and coasts, act as shelterbelts and protect watersheds; restoration plantings rehabilitate degraded and mined land; and amenity and urban plantings provide shade and recreation. Plantations are also central to many climate commitments, as they sequester carbon while they grow and supply wood that can substitute for more carbon-intensive materials. The role chosen determines the species, intensity and regime, and many plantations combine more than one role.
The advantages of plantations include high productivity per hectare, uniform raw material suited to industry, short rotations that give earlier returns, the possibility of genetic improvement, concentration of production on a small area which can spare natural forests, and rehabilitation of degraded land. Concerns include the conversion of natural forests, grasslands and other ecosystems to plantations; high water use; nutrient depletion and soil erosion; pest and disease outbreaks in uniform stands; reduced biodiversity; and conflicts over land with local people. Whether a plantation is beneficial depends on what it replaces, how it is managed and who benefits, themes taken up in the later chapters.
Plantation forestry has a long history on several continents. Teak was planted on a large scale in Java and in South Asia from the nineteenth century, and the taungya system, in which farmers raised food crops between young teak for the first years in return for planting and weeding the trees, spread from Myanmar to much of tropical Asia and Africa. In western Europe, conifers such as spruces, pines and larches were planted widely from the nineteenth and twentieth centuries to restore degraded land and build national timber reserves. In the southern hemisphere, countries with few productive native softwoods turned to exotic species: radiata pine in New Zealand and Chile, pines and eucalypts in South Africa and Australia, and eucalypts in Brazil, where they were planted first for railway fuel and later for charcoal, pulp and panels. Public subsidies, tax incentives and state planting drove much of this expansion.
From the 1970s, social and farm forestry programmes in South Asia, East Africa and elsewhere encouraged villagers and farmers to plant trees, and in the late twentieth century China began very large afforestation programmes. Today two trends stand out. First, much industrial wood in many countries comes from trees grown by farmers and smallholders, often fast-growing eucalypts, poplars, acacias, casuarinas and bamboo supplied to paper, plywood and board industries. Second, public plantations in or near natural forest areas are shifting towards restoration, native species and protection, while industrial production concentrates on dedicated estates and farm land. Many national policies now aim to raise plantation productivity on existing land so that wood demand can be met without clearing natural forest.
The first decision in plantation forestry is the choice of species, and then of provenance, seed source or clone, matched to the site and to the product. Site factors include climate (rainfall amount and distribution, temperature extremes, frost, drought length), soil (depth, drainage, texture, fertility, pH, salinity) and topography. Product requirements include fibre properties for pulp, wood density and stability for sawn timber and veneer, durability for poles and posts, and calorific value for fuel. Economic factors include growth rate, rotation length, market demand and price, and establishment cost. Social factors include local acceptance, the needs of farmers and the risk of invasiveness.
The main industrial plantation genera worldwide are Eucalyptus (and Corymbia), Pinus (radiata, elliottii, taeda, caribaea, patula and others), Acacia (mangium, auriculiformis, mearnsii and hybrids), Populus, Tectona (teak), Gmelina, Cunninghamia (Chinese fir), Cryptomeria, Picea and Pseudotsuga. The regional mix differs: eucalypts and pines dominate in South America and southern Africa; Acacia mangium, its hybrids and eucalypts in South-East Asia; Chinese fir, eucalypts and poplars in China; spruces, pines and poplars in Europe and North America; and eucalypts, poplars, casuarinas, Melia dubia, Gmelina, Leucaena, teak and bamboos on farms and estates in South Asia, as described in silviculture of species. Species trials, provenance trials and clonal tests, described in forest genetics and tree improvement, provide the evidence for choice.
Improved planting stock is the single largest source of productivity gains in modern plantations. Seed from seed orchards gives moderate gains with broad genetic diversity; selected clones, propagated by rooted cuttings or tissue culture, give larger and more uniform gains because they capture the whole genetic value of selected trees, and interspecific hybrid clones combine traits such as the growth of one eucalypt species with the disease resistance of another. Clonal eucalypt forestry in Brazil, which began in the 1970s, and later in India, South Africa, China and elsewhere, has roughly doubled productivity compared with unimproved seed in some programmes.
Clones must be tested on representative sites, because genotype by environment interaction is often strong, and deployed in ways that limit risk: using several clones, in mosaics of monoclonal blocks or in mixtures, replacing clones as new pests appear, and maintaining a broad breeding population. Planting a single clone over large areas has led to severe losses when a new pest or disease appeared, as when the eucalypt gall wasp spread through susceptible clones in Asia, Africa and the Middle East, so clone diversity is a key part of plantation risk management.
Exotic species dominate industrial plantations because a few genera grow very fast, have been domesticated through decades of breeding, and often escape their native pests for a time. Native species have advantages: they are adapted to local conditions, support more native biodiversity, are culturally accepted, and carry no risk of invasion. Their disadvantages are usually slower growth, less domestication and less market development. Many countries now promote native species for restoration and mixed plantations, and research on domesticating fast-growing native species is increasing. The choice should weigh productivity against ecological and social values for each site.
Most industrial plantations are monocultures, but mixtures of two or more species are attracting interest. Mixtures of a nitrogen-fixing species, such as an acacia, with a non-fixing species, such as a eucalypt, have in some trials produced more total biomass than either species alone, because the fixer improves nitrogen supply; other mixtures combine species that use light or soil differently. Mixtures may also reduce pest and disease risk, spread market risk across products, and support more biodiversity. Their drawbacks are greater complexity in establishment, tending and harvesting, the need to match growth rates so that one species does not suppress the other, and less certainty about yields. Results vary greatly between species combinations and sites, so mixtures must be tested locally.
Intensive plantations begin with thorough site preparation to remove competing vegetation, manage harvest residues, and give each tree a favourable rooting zone. Methods include clearing or chopping of vegetation and slash; burning, where permitted; herbicide application before planting; ripping or subsoiling to break compacted layers; mounding or bedding on wet sites; and cultivation of planting lines or pits. In second and later rotations on plantation land, residue management matters: retaining branches, bark and needles on site conserves nutrients and organic matter, whereas burning or removing them for bioenergy can deplete the site over several rotations. Site preparation intensity should match the site, since unnecessary disturbance causes erosion and nutrient loss, as discussed in nursery and plantation establishment.
Fast-growing plantations take up large amounts of nutrients, and many plantation soils, especially old, weathered tropical soils and sandy soils, are poor. Fertiliser at planting, often phosphorus with some nitrogen and potassium, placed near each seedling, speeds early growth and canopy closure; micronutrients such as boron are added where deficient. Later fertilisation, for example nitrogen and phosphorus in mid-rotation pine plantations of the south-eastern United States, or potassium and boron in some Brazilian eucalypt plantations, is applied where trials show a response. Fertiliser decisions are based on soil and foliar analysis and field trials, as described in stand tending. Nitrogen-fixing species, either in mixtures (such as eucalypts with acacias) or in rotations, can reduce nitrogen fertiliser needs.
Competition from weeds, especially grasses, is one of the main causes of poor growth and failure in young plantations. In eucalypt plantations, uncontrolled weeds in the first year can reduce early growth severely, and the losses persist for the whole rotation. Intensive programmes therefore keep plantations largely weed-free until canopy closure, by herbicides where permitted, by mechanical cultivation between rows, by manual weeding around trees, and by mulching. Weed control is most cost-effective in the first one to two years. Herbicide use is regulated nationally and restricted by certification standards, and must protect water and workers. Once the canopy closes, the trees suppress most weeds.
In intensive plantations, the quality of planting and early care decides much of the final yield. Uniform, well-hardened planting stock of the right clone, planted at the right depth with roots undamaged, in well-prepared soil at the start of the rains, with fertiliser placed near the plant and weeds controlled, gives high survival and uniform early growth. Gaps and weak plants are replaced quickly, within the first season, because late replacements are suppressed. Companies track survival, uniformity and early height as key performance indicators; poor uniformity at establishment usually persists as lower stand productivity at harvest. The practical techniques are described in forest nursery and plantation establishment.
Initial spacing determines the number of trees per hectare, the time to canopy closure, the size and branchiness of trees, the need for thinning, and costs of planting and tending. At a square spacing of 2 × 2 metres there are 2,500 trees per hectare; at 3 × 1.5 metres, 2,222; at 3 × 3 metres, 1,111. Close spacing gives early canopy closure, weed suppression, natural pruning and many small trees, suitable for pulpwood, poles and biomass; wide spacing gives fewer, larger trees with bigger branches, suitable for sawlogs when combined with pruning, and leaves room for intercrops in agroforestry. Spacing trials, including systematic designs such as the Nelder wheel, in which spacing changes gradually along radial spokes, are used to find the best spacing for a species, site and product.
Productivity is expressed as mean annual increment (MAI), the total volume produced per hectare divided by the age of the stand, and current annual increment (CAI), the volume added in a particular year. A stand with 180 cubic metres per hectare at 12 years has an MAI of 15 m³/ha/yr. In a typical even-aged stand, CAI rises to a peak and then falls; MAI rises more slowly and reaches its maximum when it equals CAI. The rotation that maximises volume production per hectare is the age at which MAI is at its maximum, called the rotation of maximum volume production or biological rotation. Financial rotations, which maximise net present value or land expectation value, are usually shorter, because of the cost of capital, and technical rotations are set by the product size required. Growth and yield relationships are covered in forest mensuration and growth and yield modelling, and financial rotations in forest economics and valuation.
Plantation productivity varies enormously. Clonal eucalypt plantations in Brazil commonly average about 35 to 45 m³/ha/yr, among the highest in the world. Radiata pine in New Zealand and Chile and loblolly pine in the south-eastern United States often reach about 20 to 30 m³/ha/yr. Eucalypt plantations in drier or less intensively managed regions, for example parts of South Asia and East Africa, are often reported in a wide range, from under 10 to over 20 m³/ha/yr, with the higher values from good clones on good sites with good management; teak plantations typically produce less than 15 m³/ha/yr. These figures are indicative only. Productivity depends on climate, especially water availability, soil fertility, genetic material, establishment quality, weed control, nutrition and protection; closing the gap between average and attainable productivity is a major aim of intensive management.
Comparing regimes by MAI shows how rotation choice affects production. Suppose a clonal eucalypt stand has 90 cubic metres per hectare at 5 years, 150 at 7 years and 190 at 10 years. Its MAI is 18, 21.4 and 19 m³/ha/yr respectively, so of these ages the 7-year rotation gives the highest average production per hectare per year; volume production would be maximised by harvesting near the age at which MAI peaks. A financial analysis might still favour a shorter or longer rotation, depending on the price of wood by size, the cost of replanting or coppice management, and the discount rate. Such comparisons, made with local growth data, guide rotation decisions.
Pulpwood regimes aim to produce the maximum volume of fibre of suitable quality at the lowest cost per tonne. They use fast-growing species or clones with suitable fibre and wood density, close spacing (often around 1,100 to 2,500 trees per hectare), intensive establishment, no pruning and usually no thinning, and short rotations: about 5 to 8 years for tropical eucalypts and acacias, longer for pines in temperate regions. Stands are clear-felled and either coppiced, as with eucalypts, or replanted with improved stock. Wood properties of interest include basic density, which affects pulp yield per cubic metre, and fibre length and wall thickness, which affect paper properties. Pulpwood regimes are relatively simple and their economics depend on yield, distance to the mill and the price paid.
Sawlog regimes aim to produce large, straight logs with few knots for sawn timber. They use wider initial spacing or early thinning to concentrate growth on selected crop trees, pruning to produce clear wood where markets reward it, commercial thinnings that give intermediate income, and longer rotations, roughly 20 to 35 years for fast-growing pines and much longer for teak and other hardwoods. The New Zealand radiata pine regime is a well-known example: planting at moderate density, early selection of crop trees, pruning in two or three lifts to about six metres, early waste or production thinning to a final stocking of a few hundred stems per hectare, and clear felling at around 25 to 30 years. Teak sawlog regimes in South and South-East Asia, West Africa and Central America use mechanical then selective thinnings and rotations of several decades for high-quality heartwood. Pruning and thinning techniques are described in stand tending and thinning.
Veneer or peeler logs, used for plywood and veneer, need logs of adequate diameter, roundness and straightness, often with clear wood on the outside. Poplars in Europe and Asia, eucalypts, Gmelina and Melia dubia in tropical Asia, and some pines are grown for peeling, often on short to medium rotations, as rotary lathes can now peel small logs efficiently down to small cores. Multi-product regimes produce several assortments from one stand: thinnings for pulp, poles or posts, and final crop logs for sawn timber or veneer, with the upper stem and branches for fuel or biomass. Choosing between regimes is a financial decision that depends on markets, prices for each assortment, costs, risks such as storms or fire over longer rotations, and the grower's need for early income; smallholders often prefer short rotations for that reason.
Eucalypt plantations are often managed for one or two coppice rotations after the planted crop. After clear felling, each stump produces many sprouts; these are reduced (singled or thinned) to one or two of the best shoots per stump within the first year, so that growth is concentrated on stems of good form. Coppice rotations often yield as much as or slightly less than the planted crop, with yields declining over successive coppice cycles as stumps die or lose vigour. Because improved clones are released regularly, many companies replant with new clones after one coppice rotation rather than keep older genetic material. Stump height, timing of harvest and protection of new sprouts from grazing affect coppice success.
Wood from fast-grown, short-rotation plantations differs from that of slow-grown natural forest trees. It contains a high proportion of juvenile (corewood) wood, formed near the pith in the early years, which in many species has lower density, shorter fibres, larger microfibril angle and greater longitudinal shrinkage, giving lower stiffness and more distortion on drying. Short-rotation teak has more sapwood and less of the colour and durability of old teak. These properties matter little for pulp and energy but limit structural and appearance uses. Plantation managers address them by breeding for density and stiffness, by longer rotations for high-value products, and by processing technologies such as engineered wood products that make good use of small, uniform logs. Wood properties are covered in detail in wood anatomy and properties.
Short-rotation coppice (SRC) is the cultivation of fast-growing species that resprout after cutting, planted at high density and harvested every few years for biomass. In Europe, willows and poplars are planted as unrooted cuttings at high densities, of the order of 10,000 or more cuttings per hectare, often in twin rows to allow machinery, and harvested every two to five years with specialised harvesters that chip the stems; the stools resprout and plantations last for about two decades before replanting. Yields commonly reported for well-managed willow and poplar SRC are of the order of 8 to 12 oven-dry tonnes per hectare per year, varying with site, clone and climate. Eucalypt coppice in the tropics and subtropics, harvested every few years for pulp or energy, is a related system. SRC needs fertile, moist land, weed control in establishment, and markets for chips.
Energy plantations grow wood for fuel, charcoal, heat and electricity. Wood has a calorific value of roughly 18 to 20 gigajoules per oven-dry tonne, so a plantation yielding 10 oven-dry tonnes per hectare per year produces roughly 190 gigajoules of energy per hectare per year at 19 GJ per tonne. Energy plantations in the tropics and subtropics have used species such as Leucaena leucocephala, Calliandra calothyrsus, Casuarina, eucalypts, Acacia species and bamboos, on community land, degraded land and farms, for household fuel, brick kilns, tea and tobacco curing, industries and small biomass power plants. Large eucalypt plantations in Brazil supply charcoal for iron and steel making, while in northern and central Europe willow and poplar coppice feeds heat and power plants. Prosopis juliflora was widely planted for fuel in dry regions of South Asia and Africa but has become an aggressive invader of rangelands and wetlands in many of them, a warning about introducing hardy exotics. Dendrothermal power, generating electricity from wood grown in dedicated plantations, has been tried but often struggled with the cost and reliability of feedstock supply. Fuelwood plantations on village commons, promoted under social forestry programmes in South Asia and parts of Africa in the 1970s and 1980s, met with mixed success, as many farmers preferred to sell poles and pulpwood rather than produce fuel for local use.
Bioenergy from plantations can reduce fossil fuel use, but its benefits depend on the land it occupies, the carbon stored before planting, the inputs of fertiliser and fuel, and the efficiency of conversion. Converting natural forests, peatlands or productive farmland to energy plantations can release more carbon and cause more harm than the energy saves; using degraded land, residues and well-designed coppice systems gives the best results. Repeated harvest of whole stems and branches every few years removes nutrients, so fertilisation or return of ash may be needed. Policies and certification for sustainable biomass set criteria for land use, carbon and biodiversity.
Plantations of one species, often of one or a few clones, on large areas of uniform age, create conditions in which pests and pathogens can spread rapidly. Exotic species may at first escape their native enemies, but over time pests and pathogens arrive through trade or adapt from local hosts, a process that has been documented repeatedly as plantation estates expand. Stress from planting off-site, drought, nutrient deficiency or climate change makes trees more susceptible. Once established, a pest in a monoculture can cause damage over a whole region within a few years.
Examples from around the world show the pattern. The eucalypt gall wasp Leptocybe invasa, native to Australia, spread through eucalypt plantations in Asia, Africa and elsewhere in the 2000s, severely damaging susceptible clones in South Asia, the Middle East and Africa. Myrtle rust (Austropuccinia psidii) threatens eucalypts and other Myrtaceae as it spreads around the world. The woodwasp Sirex noctilio, accidentally introduced from Europe, has killed large numbers of pines in plantations in the southern hemisphere and is controlled biologically with a parasitic nematode and parasitoid wasps. The pine wood nematode (Bursaphelenchus xylophilus), introduced from North America, has devastated pines in East Asia and has spread to Portugal. Dothistroma needle blight affects radiata pine. Ceratocystis wilt and heart rots affect Acacia mangium plantations in South-East Asia. In tropical Asia the teak defoliator (Hyblaea puera) and in poplar-growing regions leaf rusts and defoliating insects are among the main plantation problems, as described in silviculture of species and forest entomology and pathology.
Plantation health is managed by prevention as much as by cure. Biosecurity at borders and in nurseries reduces the arrival and spread of new pests. Genetic diversity reduces risk: planting several species or clones, in mosaics or mixtures, and maintaining a breeding programme that can deliver resistant material when a new threat appears. Good silviculture, matching species to site, adequate nutrition and timely thinning keeps trees vigorous. Monitoring and early detection, followed by integrated pest management that combines biological control, cultural practices and, where necessary and permitted, chemical control, limits damage. Landscape design that breaks up large uniform blocks with native vegetation and different age classes also slows spread and supports natural enemies.
Besides pests and pathogens, plantations face abiotic risks. Fire is a major threat in pine and eucalypt plantations in seasonally dry climates, where uniform, continuous fuel and resinous or oily foliage allow fires to spread rapidly; firebreaks, fuel management, early detection and landscape mosaics reduce the risk. Wind can cause extensive damage in shallow-rooted, tall, recently thinned or uniformly aged stands, especially in storm-prone regions, as experienced in European spruce plantations. Drought, increasingly frequent with climate change, causes growth losses and mortality, particularly where species or clones have been planted on sites at the dry edge of their tolerance. Choosing species and clones with margins of safety for the future climate, and spreading risk across species, ages and locations, is part of plantation planning.
Fast-growing plantations use large amounts of water, especially where trees with deep roots and high leaf area replace grassland or shrubland. Catchment studies around the world have shown that afforesting grassland usually reduces streamflow, with the largest absolute reductions in high-rainfall areas and the largest proportional reductions in drier ones, and that groundwater recharge may also fall. Some countries regulate this impact directly: South Africa, where pines and eucalypts replaced grasslands in important catchments, licenses new plantations as a stream flow reduction activity under its 1998 water law, and other countries use zoning or catchment limits on afforestation. Concern about eucalypt water use has been strong in South Asia, southern Africa, the Iberian Peninsula and elsewhere; the evidence indicates that eucalypts use water in proportion to their growth, not unusually per unit of wood, but that fast plantations in low-rainfall areas or near wells and streams can reduce water availability. Siting plantations away from water-scarce areas and riparian zones, keeping buffer strips and limiting the share of a catchment under plantations reduce the impact.
Plantations can improve degraded soils by adding organic matter and protecting against erosion, or degrade soils by nutrient export at harvest, erosion during site preparation and early growth, compaction by machines and, in some cases, acidification. Short rotations and whole-tree harvest remove more nutrients than long rotations with stem-only harvest, so nutrient budgets, residue retention and fertilisation are needed to maintain productivity over successive rotations. Long-term site productivity research has shown that productivity can be maintained or improved when residues are retained and nutrients replaced, but can decline where they are not.
Plantations usually support fewer native species than the natural forests or grasslands they replace, especially monocultures of exotics with closed canopies and short rotations. Their effect depends strongly on what they replace and how they are managed. Plantations on degraded land can serve as nurseries for native species, catalysing natural regeneration of native trees in their understorey, as documented in tropical studies. Practices that improve biodiversity include retaining patches of native vegetation and riparian buffers, using mixed species or native species, leaving old trees and dead wood, longer rotations in some stands, and designing landscapes as mosaics. Certification standards, such as the Forest Stewardship Council's, require conservation set-asides in certified plantations and do not certify plantations established by converting natural forest after November 1994, with limited exceptions. Replacing natural grasslands and savannas with plantations is increasingly recognised as harmful, as discussed in forest types and biogeography.
Outgrower schemes are partnerships in which a company, usually a pulp mill, panel or plywood factory, or sawmill, contracts farmers or communities to grow trees on their own land and supply the wood to the company. Typical arrangements include supply of improved seedlings or clones by the company, often at subsidised prices; technical advice on planting and management; credit or advance payments for establishment costs; and a buy-back agreement that commits the company to buy the wood at a guaranteed minimum price or at the market price at harvest. Schemes range from formal written contracts to informal arrangements. Brazil's 'fomento florestal' programmes, outgrower schemes in South Africa and other African countries, smallholder acacia and eucalypt supply to mills in Indonesia and Vietnam, and South Asian programmes linking paper and plywood industries with farmers growing eucalypts, casuarinas, Leucaena, poplar and Melia dubia are prominent examples.
For companies, outgrower schemes secure wood supply without buying land, spread risk and build relations with local communities. For farmers, they provide planting stock, knowledge, credit and an assured market, and turn marginal land into a source of income. In several countries of South and South-East Asia, farm forestry linked to industry has made farm trees a major source of industrial wood, and clonal eucalypt programmes linked to paper mills have been widely studied, as have the eucalypt outgrower schemes of KwaZulu-Natal in South Africa.
Problems arise when prices fall below expectations, when contracts are unclear or unenforced, when companies fail to buy as promised or farmers sell to others offering higher prices (side-selling), when farmers lack bargaining power, and when tree planting competes with food crops on scarce land or concentrates benefits among larger farmers. Long rotations make farmers wait years for income, so short-rotation species are preferred by smallholders. Price volatility, as with farm-grown poplar and eucalypt in several regions, can cause booms and busts in planting.
Successful schemes have clear, fair contracts that farmers understand; transparent price-setting, often linked to market prices with a floor; reliable supply of good planting stock suited to local sites; extension support; access to credit or insurance; reasonable harvesting and transport arrangements; and farmers' organisations that can negotiate. Policies that ease the felling and transport of farm-grown trees, such as the removal of transit restrictions for many farm species and for bamboo grown outside forests, help farmers sell. Monitoring outcomes for farmers' incomes and for land use is part of responsible corporate practice and of certification for company supply chains.
Forest management certification, under schemes such as the Forest Stewardship Council and the Programme for the Endorsement of Forest Certification, is increasingly demanded by buyers of pulp, paper and wood products. Certification of large company plantations is common; certification of smallholders and outgrowers is harder because of the cost and paperwork for many small owners. Group certification, in which a company, cooperative or association manages certification for many small growers under one certificate, has made certification feasible for farm forestry in countries in South America, Africa and Asia, where groups of farmers supplying wood-based industries have been certified. Certification standards for plantations cover legality, worker and community rights, environmental safeguards, chemical use and conservation set-asides, and are described further in certification and sustainable forest management.
Bamboo plantations grow fast, are harvested annually after establishment without replanting, protect soil with their dense root and rhizome systems, and supply raw material for construction, pulp, panels, crafts, food and energy. They suit smallholders because they can be harvested every year once established, and they grow on marginal land and field boundaries. Bamboo plantations are concentrated in Asia, Latin America and Africa. China has the most developed bamboo plantation industry, based largely on moso bamboo (Phyllostachys edulis), a running bamboo managed intensively for timber and shoots. In the northern Andes, Guadua angustifolia is grown for construction; in East Africa, highland bamboo (Yushania alpina) and lowland bamboo (Oxytenanthera abyssinica) are planted and managed; and South and South-East Asia grow many clumping species. Several countries run national bamboo programmes that support nurseries, plantations and processing, and some have changed their forest laws so that bamboo grown on private land is not regulated as a tree, which makes it easier for farmers to harvest and sell it.
Species are chosen for the product and site: Dendrocalamus strictus for dry areas and poles, Bambusa bambos and B. tulda for moist sites, Dendrocalamus asper and D. giganteus for large culms and shoots, Bambusa balcooa and D. hamiltonii in the humid hills of north-eastern South Asia, Guadua angustifolia in tropical America, and others, as described in silviculture of species. Planting stock is raised from seed when available, from offsets, culm or branch cuttings, by macroproliferation, or by tissue culture, as described in forest biotechnology and propagation. Clumping bamboos are planted at the onset of the rains in pits, commonly at spacings such as 4 × 4 to 6 × 6 metres or wider for large species, with fertiliser and organic manure, irrigation in dry spells where possible, and weeding and protection from grazing and fire.
Harvesting begins a few years after planting, when the clump has established and culms have reached mature size; thereafter mature culms, usually three years old or more, are harvested every year or on a short cycle, leaving young culms to sustain the clump, and congested clumps are cleaned. Yields of well-managed bamboo plantations can be substantial but vary widely with species, site and management, and reported figures should be compared carefully. Gregarious flowering is a risk for plantations of a single flowering cohort; mixing species or sources of different flowering cohorts reduces it. Markets, processing facilities and transport determine whether bamboo plantations pay, so plantation programmes are increasingly linked with processing units and farmer producer organisations.
The economics of bamboo plantations depend on the time to first harvest (usually a few years), the annual yield of saleable culms once established, the price of culms or processed products, the cost of harvesting and transport, and the life of the plantation, which can be several decades if clumps are well managed and do not flower. Because bamboo is bulky and has low value per tonne in raw form, primary processing near the plantation, into splits, slivers, sticks, mats or charcoal, adds value and reduces transport costs. Farmers benefit most when they are organised into producer groups linked to processors and markets, and when transit rules allow free movement of farm-grown bamboo. Uncertain markets and long waits before first income have limited adoption in some regions despite subsidies.
A student should be able to define planted and plantation forests, explain how species and clones are chosen, describe intensive establishment, calculate trees per hectare and MAI, explain the relation of MAI and CAI to rotation, contrast pulpwood, sawlog and veneer regimes, describe short-rotation coppice and energy plantations, explain monoculture risks and environmental effects, and describe outgrower schemes and bamboo plantations. Visits to clonal plantations, company nurseries and farm forestry areas make these concrete.
A forester in a plantation company or forest development corporation plans site preparation, fertilisation and weed control, selects clones for each site, sets spacing and regime, monitors survival, growth and pests, organises harvests and coppice management, and works with outgrower farmers on supply of planting stock, technical advice and buy-back arrangements. In public service the forester manages departmental plantations and supports farm forestry and bamboo programmes.
A senior plantation manager designs estate-wide strategies: species and clone portfolios, rotation and regime choices based on markets, risk management for pests and fire, landscape design with conservation areas, water and soil safeguards, certification compliance, outgrower programme design, and investment decisions. Such a manager also engages with communities and regulators on land and water issues.
A researcher studies plantation productivity and sustainability: ecophysiology and water use, nutrition and long-term site productivity, genotype by environment interaction of clones, pest and disease epidemiology in monocultures, carbon and biodiversity outcomes, and the economics and social impacts of outgrower schemes. Such work underpins the next generation of plantation management guidelines.
This manual describes plantation principles and gives indicative figures; it does not give species- or clone-specific yield tables, fertiliser prescriptions, herbicide products or company programme details, which change and must be taken from local sources. Productivity figures are approximate global or national ranges. Detailed economics of rotations and regimes belong to forest economics and valuation, and growth modelling to growth-yield-modelling. Mixed-species plantations and restoration plantings are treated only briefly. National data on plantation area and productivity vary widely between sources and are not tabulated.
Original practice questions written to the syllabus and pattern of the exams named in each question's examTags. They are not past papers and do not reproduce any board's questions.
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