abiotic
Relating to things that are not alive. Used to describe the physical attributes of a land-use system (for example, soil, climate).

acid soil
Soil with a pH of < 7.0.

afforestation
1. Conversion of bare land into forest land by planting of forest trees.
2. The planting of a forest crop on land that has not previously, or not recently, carried a forest crop.

agrarian policy
A policy concerned with the land or landed properties.

agricultural system
A system with agricultural outputs and containing all the major components.

agroecological zone
1. A major area of land that is broadly homogeneous in climatic and edaphic factors, but not necessarily contiguous, where a specific crop exhibits roughly the same biological expression.
2. Zones of similar agricultural performance as defined by soil and climate.

agroecosystem
The collection of physical, environmental, economic and social factors that affect a cropping enterprise.

agroforestry system
A land-use system in which woody perennials (trees, shrubs, palms, bamboos) are deliberately used on the same land management unit as agricultural crops (woody or not), animals or both, either in some form of spatial arrangement or temporal sequence. In agroforestry systems there are both ecological and economic interactions between the different components.

agronomy
That part of agriculture devoted to the production of crops and the management of the soil on which they are grown. The scientific utilization of agricultural land.

agropastoral system
A land-use system in which crops and livestock (but not trees) are the only components.

agrosilvicultural system
An agroforestry system for the concurrent production of agricultural crops (including woody perennial crops) and forest crops. The forest crops serve in either a productive or a service role. Woody perennial and agricultural crops are chosen first for their productive capacity.

agrosilvipastoral system
Any agroforestry system that includes trees or shrubs and herbaceous food crops and pastures and animals.

alley cropping
An agroforestry intercropping system in which species of shrubs or trees are planted at spacings relatively close within row and wide between row, to leave room for herbaceous cropping between, that is, in the 'alleys' (syn: hedgerow intercropping).

alternative farming
Farming not in the current, conventional manner; for example, not using fertilizers and pesticides, or by using intermediate technology and renewable energy sources.

annual plant
A plant that completes its life cycle within one year.

apiculture
Beekeeping.

aquaculture
Fish farming. In a broad sense, producing any product under water, for example, algae (seaweed), Crustaceae (shrimp).

aquasilvicultural system
An agroforestry system that combines trees with the raising of aquatic animals.

arable land
Refers to land under crops, land under temporary meadows for mowing or pasture, land under market and kitchen gardens (including cultivation under glass) and land temporarily fallow or lying idle. Hence 'arable farming'.

arboretum
A collection of specimen trees, preferably growing close to a nursery, from which seeds and cuttings can easily be gathered.

arboriculture
A general term for the cultivation of trees.

asexual reproduction
Propagation of plants from vegetative parts, such as stems, leaves or roots; or from modified stems such as bulbs, tubers, rhizomes and stolons. This is accomplished without union of gametes (syn: asexual regeneration).

B

bamboo
A vegetation type consisting of woody graminaceous species from the subfamily Bambusoideae. Found as dense thickets or forest in the high-altitude tropics that have only a sparse ground cover of herbs, grasses, mosses and ferns. Sometimes also in the lowlands.

barrier hedge
A hedge planted so as to prevent runoff.

biennial
1. A plant that ordinarily requires two years, or at least part of two seasons, with a dormant period between growth stages, to complete its life cycle.
2. A plant that flowers only in the year following that in which it germinates from seed.

biodiversity
The level of abundance of life forms co-existing in a given environment.

biological control
1. Using living organisms to reduce populations of pest organisms.
2. Any of a wide variety of substances or methods used in pest control that emphasize the use of living organisms or products derived directly from them.

biomass
Strictly, the quantity of biological matter present on a unit area; may be 'total' or often only 'above-ground'. May be separated into plant and animal mass, or further divided into the mass of standing crop, or the tree portion of a stand, and then into foliage, branch, stem, flowers, and so on.

biotic
The influence of animals and plants on associated plant or animal life as contrasted with climatic influences and edaphic (soil) influences.

block
1. A set of experimental units under treatment or observation, which have been grouped to minimize environmental effects or initial differences between units in respect of the variables being studied, for example, a set of contiguous or non-contiguous experimental plots initially giving the same experimental response.
2. In forestry, the primary subdivision and major territorial unit of a forest estate, generally bounded by natural features. It is divided into compartments.

bole
1. Tree stem once it has grown to substantial thickness, capable of yielding timber or large poles.
2. The trunk of a tree. It may extend to the top of the tree as in some conifers, or it may be lost in the ramification of the crown, as in deciduous species.

broadleaved
Trees other than conifers that have (usually but not always) flat, broad leaves. Ovules are found in an ovary, and all reproductive organs appear in flowers. They belong to the angiosperm group of plants.

browse
Leaves, small twigs and shoots of shrubs, seedling and sapling trees, and vines available for forage for livestock and wildlife.

browsing
The feeding on the above-ground parts of trees and shrubs (buds, shoots and leaves) by livestock or wild animals.

brush
1. Undergrowth, often of a thicket and including the small trees and shrubs.
2. Material such as twigs cut from undergrowth.

buffer zone
An area around a forest, national park, or any other conserved place that provides the local community with products that they would otherwise take from the forest, or that provides an opportunity to produce alternative products.

bund
1. A barrier on the surface of the soil on sloping land to prevent runoff and soil erosion.
2. The arrangement of organic material, for example, agricultural waste or soil, in lines along the contours of a slope, to control runoff or erosion.

bush
1. A general term for low tree–high grass vegetation occurring in semi-arid or seasonally arid regions. Can be further described by the dominant species present, for example, 'acacia bush', 'combretum bush'.
2. A low, well-branched shrub.

bush fallow
The natural vegetation that arises when land is left uncultivated for some time. Composed of small trees, shrubs, grasses (and sedges) and herbaceous plants. Bush fallow may be grazed or browsed and firewood collected from it before it is returned to cultivation.

 C

canopy
The assemblage or volume of leaves of all ages supported by branched stems that form the photosynthetic layers of a tree or crop.

cash cropping
Growing crops for sale either to a market or to agents, or at the 'farm gate'.

clear cutting
1. Strictly, the removal of an entire standing crop of trees. In practice, may refer to exploitation that leaves much unsaleable material standing. Also termed 'clear felling'.
2. An area from which the entire timber stand has been cut. Removal of the entire stand in one cut. Reproduction is then obtained with or without planting or artificial seeding.

clearing
[noun] A relatively small area within a forest that has no trees.
[verb] To dispose of undergrowth and vegetational debris that is left after trees have been felled and trimmed. Sometimes done by a burn. Clearing is also done by removal or controlled burning around forests, villages, homes or trees to act as a firebreak.

closed forest
Forest where trees are the dominant life form and the canopy is closed.

codominant trees
Trees with crowns forming the general level of the crown cover and receiving full light from above but comparatively little from the sides, usually with medium-sized crowns and more or less crowded on the sides.

community forestry
Forestry developed in areas marginal to agriculture, with many members of the community being landless or small-scale farmers, often characterized by ecological and cultural diversity and the employment of traditional technologies. Communal land development is basic to this type of forestry.

compost
1. In plant nursery work, a mixture of inorganic and organic materials, perhaps with some soil of a particular suitable kind, in which seeds can be readily germinated or seedlings or young plants grown. Particular composts are made for particular purposes, and fertilizers are often added.
2. A pile of decomposing organic matter of plant or animal origin. Soil and other amendments such as lime, nitrogen and phosphorus may be mixed with the organic matter.
3. Organic residues, or a mixture of organic residues and soil that have been made into a pile and allowed to undergo biological decomposition.

conifers
Trees that usually but not always have needle leaves or scale leaves and that bear separate male and female cones. They are usually, but not always, evergreen. Some, for example, larch, are deciduous. Conifers belong to the class Gymnospermae.

conservation
The protection, use and improvement of natural resources according to principles that will assure their highest economic and social benefits.

contour
Linear demarcation of the land surface that indicates places of equal elevation; the lines on a map that connect these points.

contour cropping
Sowing a crop in rows or strips so that these follow along a contour.

contour furrow
A furrow ploughed on the contour on pasture or rangeland to prevent soil loss and so as to allow water to penetrate the soil; sometimes used in planting trees and shrubs on the contour.

contour tillage
The cultivation of land along the lines of uniform elevation, or contour lines, to reduce erosion.

coppice
1. A method of cutting certain species of trees to encourage them to regrow from the remaining stump. A tree that coppices readily does not require frequent replanting and is, therefore, useful for producing fuel and poles.
2. Shoot developed from a dormant bud on a main trunk.
3. A small wood regularly cut over for regrowth.

corm
A specialized part of a stem; a short, enlarged base of a stem where food is stored.

cropping pattern
The yearly sequence and spatial arrangement of crops, or crops and fallow, on any given area.

cropping season
The period during the year when the environment is favourable for the growth of agricultural crops. In regions that have bimodal rainfall, there will be two such seasons. Trees may grow at other, less favourable, times.

cropping system
1. The cropping patterns used on a farm and their interaction with farm resources, other farm enterprises and available technology.
2. The crop production activity of a farm. It comprises all cropping patterns grown on the farm and their interaction with farm resources, other household enterprises, and the physical, biological, technological and social economic factors or environments.
3. A land-use unit comprising soils, crops, weeds, pathogens and insect subsystems, which transforms solar energy, water, nutrients, labour and other inputs into food, feed, fuel and fibre. The cropping system is a subsystem of the farming system.

crop rotation
The growing of different crops on the same land in recurring succession.

crown
1. A tree canopy, the upper part of a tree or other woody plant carrying the main branch system and foliage, and surmounting at the crown base a more or less clean stem.
2. The branches and foliage of a tree or the upper portion of a tree. The leaves as foliage are an outgrowth of the vascular system and are mainly concerned with photosynthesis. The branches join the stem or other branches.

culm
The stem of grasses and bamboos, usually hollow except at the swollen nodes.

cultural practices
Crop care practices including land preparation, seed selection, weed control, fertilizer and insecticide application, and water control in the field.

cutting
A detached part of a plant (for example, stem, root or leaf) that is placed in suitable conditions to promote rooting and the subsequent production of a new leafy shoot. Stem cuttings can be 'hardwood' (secondarily thickened from previous seasons' tissue), 'semi-hardwood' (mature current or last season's tissue) or 'softwood' (young tissue from the current season). They can be cut nodally or internodally

 D

deciduous
1. Of leaves, bark, and so forth, falling regularly at the end of a growth period, or in the tropics, prior to one.
2. Of a leaf, falling at the end of one season of growth or life. Of a perennial plant, losing its leaves (or a proportion of them) at the end of a season's growth.

deciduous forest
A forest composed of trees that shed their leaves at some season of the year. In tropical areas trees may lose their leaves during the hot season to conserve moisture. Trees of a deciduous forest in cool areas shed their leaves during the autumn to protect themselves against the cold and frost of winter. Deciduous forests produce valuable hardwood timber, such as teak and mahogany from the tropics, and oak and beech from the cooler areas.

 E

ecofarming
Farming land by using practices that maintain biological diversity and conserve the resource base.

ecology
1. The study of the totality or patterns of relations between organisms and their environment.
2. The study of the interactions of living things, from ecos, the Greek word for 'living earth'. Certain plants and animals require specific conditions to live well and this is often termed the ecology of that plant or animal.

ecosystem
1. The entire system of life and its environmental and geographical factors that influence all life, including the plants, the animals and the environmental factors.
2. System that includes both living (biotic) and non-living (abiotic) units to produce an exchange between them.
3. A group of organisms interacting among themselves and with their environment.

energy farming
The process of using land to grow crops, woody or otherwise, that provide fuel, for example, close-planted, fast-growing tree species such as poplar (temperate) or leucaena (tropical). These may be harvested by hand or mechanically. Hydrocarbon fuels can be extracted from other kinds of plants, for example, from some Euphorbia species.

enriched fallow
A form of agroforestry in which useful, mainly woody species are sown or planted before cultivation ceases, or at the time it does, so that during the fallow period, or when the land is next cleared for cultivation, products are available for household use or market that would not otherwise have been there (for example, fruits, bamboos, rattans, medicinals).

erosion
The detachment and movement of the solid material of the land surface by wind, moving water or ice, and by such processes as landslides and soil creep.

establishment
The successful growth of young plants, brought about by providing them with the right site and favourable conditions.

evergreen
A plant remaining green in its dormant season and so applied to plants that are green throughout the year. Properly applied to plants and not to leaves, as it is due to the persistence of leaves.

exotic

Commonly used to refer to a plant or other organism introduced from a foreign country. For example, Grevillea robusta, which comes from Australia, is an exotic tree species in Kenya. Strictly, however, the term refers to a plant grown anywhere outside its natural range.

ex situ
From outside. When applied to tree plantations, refers to a planting site distant from the seed collection site.

 F

fallow
1. Allowing crop land to lie idle, either tilled or untilled, during the whole or greater portion of a growing season. Tillage is usually practised to control weeds and encourage the storage of moisture in the soil.
2. Land rested from deliberate cropping, not necessarily without cultivation or grazing but without sowing.
3. State of land left without a crop or weed growth for extended period, often to accumulate moisture.

farm forestry

Growing trees for timber, poles, fuelwood on farmland. This may be done in small woodlots or as boundary plantings.

farming systems research and development
An approach to agricultural research and development that (1) views the whole farm as a system and (2) focuses on the interdependence among the components under the control of the farm household's members and how these components interact with the physical, biological and socioeconomic factors not under household control. The approach involves selecting targets, areas and farmers, identifying problems and opportunities, designing and executing on-farm research, evaluating results, and extension.

firebreak
In forestry, an existing barrier, or one constructed before a fire occurs, from which flammable materials have been removed, designed to stop or check creeping or running fires. Also serves as a line from which to work and to facilitate the movement of men and equipment in fire suppression.

fodder
Plants or plant parts eaten by browsing or grazing animals. Fodder trees include species of Acacia, Leucaena, Prosopis and many others. Normally, fodder refers to the green parts of the tree, for example, leaves or sometimes flowers and pods. Often fodder is collected and stored for future consumption.

foliage
The entire leaf mass of a tree or trees (or of plants generally).

forage
Any plant material, except commercial feedstuffs, consumed by livestock. The most common forage crops are grasses and legumes.

forage forestry
Growing close-planted, fast-growing tree species that can be mechanically harvested, such as by a forage harvester in agriculture, for wood products such as woodchips.

forest garden
A land-use form on private lands outside the village in which planted trees and sometimes, additional perennial crops occur.

forest grazing
Any situation (silvopastoral) where timber-producing trees and grazed pasture are grown together as an integrated management system, the prime objective being to increase long-term net profit per hectare. Growing pasture under trees as an alternative source of income to production thinning of timber or pulpwood.

 G

gallery forest
Vegetation, with trees and shrubs, growing alongside or close to a watercourse, lake, swamp, or the like, and often dependent on its roots reaching the watertable. Also called a riparian forest.

gene bank
For plants, any place established with the appropriate facilities and trained staff where plant germplasm can be maintained in the form of seeds or tissues or as growing plants.

germination
Growth of the embryo in the seed until the emergence of the embryonic radicle through the seedcoat. In seed testing, the capacity of the embryo to emerge from the seed coat with the essential structures indicates a potential to produce normal plants. In dry seeds, germination follows imbibition (absorbing water and swelling).

germplasm
1. The material constituting the physical basis of inheritance (seeds, cuttings, tissue cultures). The sum total of the hereditary materials in a species.
2. The sum total of the genes and cytoplasmic factors governing inheritance. The hereditary material transmitted to offspring through the germ cells.

green manure
1. A crop that is grown for soil protection, biological nitrogen reduction, or organic matter and ploughed, disked or hoed into the soil.
2. Any crop grown for the purpose of being turned under while green, or soon after maturity, for soil improvement

 H

hardwood
The timbers from broadleaved, angiosperm trees often, but not always, harder than the timber from conifers (softwoods). They are often, but not always, deciduous (Eucalyptus, for example, are hardwoods).

heartwood
1. The inner of two distinct wood layers in the trunk of many trees. The outer layer, usually lighter and moister, called sapwood, is newly formed wood with some living cells. Inside this ring of sapwood is often a darker, harder, more durable core called heartwood. A striking example of heartwood and sapwood difference is found in Dalbergia melanoxylon, which has light brown sapwood and purple black heartwood; it is often used for craft carving.
2. The wood in the centre of a tree, no longer in use for conducting water from the roots to the leaves. It is often darker in colour than the outer wood (sapwood) and may contain chemicals that make it more resistant to decay.

hedge
Bushes or shrubs or trees planted in a row and trimmed. Used to separate one piece of land from another.

hedgerow
A barrier of bushes, shrubs or small trees growing close together in a line. A hedge is similar but pruned.

homegarden
A land-use form on private lands surrounding individual houses with a definite fence, in which several tree species are cultivated together with annual and perennial crops; often with the inclusion of small livestock. There are many forms of such gardens varying in how intensively they are cultivated and their location with regard to the home, for example, village forest gardens, 'compound gardens', 'kitchen gardens'.

 I

indigenous
Native to a specified area, not introduced. An indigenous tree is one that grows naturally within a specific environment or within certain predetermined boundaries.

industrial forestry
Large-scale, commercial tree planting for timber and other wood products (for example, wood chips).

in situ
'On the site'. When applied to tree plantations, refers to seed planted in the same area as it was collected.

in vitro
In a laboratory (strictly 'in glass', that is, a test tube). For example, the digestibility of animal feeds may be estimated by appropriate chemical methods 'in vitro' in a laboratory; 'in vivo' (in the animal itself) using a fistula (narrow tube) to extract material ingested after it has been through the rumen (first stomach), or later, to see what has been absorbed; or, ultimately, by live weight gain per amount of intake.

 K

kilning
Drying wood under controlled temperature and humidity.

 L

latex
A thick white or whitish liquid produced by certain plants. For example, Antiaris toxicaria and Bridelia micrantha both have a latex sap. A more popular example is the rubber tree (Hevea braziliensis). Some types of latex can be harmful, especially if the latex gets into the eyes.

litter
Uppermost layer, on the soil surface, of loose organic debris (for example, as in forests), consisting of freshly fallen or slightly decomposed organic materials.

live fence
A way of establishing a boundary by planting a line of trees and/or shrubs (the latter usually from large stem cuttings or stumps), at relatively close spacing and by fixing wires to them. If animals are to be kept in or out, more uprights (dead sticks) can be tied to the wires. Also called a 'living fence'.

lopping
1. Cutting one or more branches of a standing tree, for example, for fuel or fodder.
2. A technique used to collect fodder for animals by cutting side branches, not the main stem. Animals can be allowed to eat the lopped branches of the tree, or they can be carried to the animals as in a zero-grazing system.

lumber
Sawn timber. A unit of measure is the 'board foot', that is, a board 12 inches long by 12 inches wide by 1 inch thick.

 M

mangroves
1. Open or closed stands of trees and bushes occurring in the tropics in inter-tidal zones, usually around the mouths of rivers, creeks and lagoons where soils are heavy textured and have a fluctuating salt content and soil level.
2. A name used collectively for the assemblage of plants, as well as to refer to individual genera or species, for example, woody members of the Rhizophoraceae, Combretaceae and Verbenaceae. These have knee-like roots that are 'pneumatophores' (roots with air spaces). Grown for wood and tannins.

miombo
A form of woodland found in southern Africa in hot, semi-arid regions with a monomodal rainfall (for example, in Tanzania, Zimbabwe, Malawi, Zambia). Rainfall is high (> 1000 mm) and soils are poor in nutrients and acid. The vegetation is dominated by slow-growing, mainly deciduous, caesalpiniaceous trees (for example, Brachystegia, Julbernardia).

mixed garden
A land-use form on private lands outside the village, dominated by planted perennial crops, mostly trees, under which annual (seasonal) crops are cultivated. When spices are grown they are called 'spice gardens'.

mixed stand
A stand in which less than 80% of the trees in the main canopy are of a single species.

multiple-use forestry
Any practice of forestry that fulfils two or more objectives of management, whether products, services or other benefits. Also called 'multipurpose forestry'.

multipurpose tree
A woody perennial that is purposefully grown to provide more than one significant contribution to the production or service functions (for example, shelter, shade, land sustainability) of the land-use system that it occupies. Also called 'agroforestry tree'.

multistorey cropping
Multispecies crop combinations involving both annuals and perennials with an existing stand of perennials. An association of tall perennials with shorter statured crop species.

multistorey system
An agroforestry system, such as a homegarden, that has a number of plant components of differing stature so that several layers of canopy are formed.

 N

nitrogen-fixing plant
A plant that can assimilate and fix the free nitrogen of the atmosphere with the aid of bacteria living in root nodules.

nodule
Nitrogen-fixing root swelling of characteristic shape and size for particular leguminous species that contain rhizobia. If the rhizobial strain is effective, atmospheric nitrogen can be fixed and is readily utilizable by the plant.

normal-aged forest
A forest composed of a series of age classes in proportions that permit sustained yield by felling under an appropriate system.

nursery stock
Shrub or tree species grown in a plant nursery for planting out elsewhere.

 O

open forest
A 'forest' where the canopy is not closed and a large proportion of the area does not carry trees.

organic farming
The production of crops from land that does not receive and has not received (for a stated period of time) any inorganic inputs (fertilizers, pesticides, and so on).

ornamental
Any tree or plant that is planted for its beauty. This does not mean that it has no other uses. For example, Chlorophora excelsa is often planted as an avenue tree along roadsides (in Uganda); its stately appearance in no way diminishes its usefulness for timber. Ornamentals with other uses in agroforestry are the Cassias and Senna spp.

overstorey
The portion of trees in a forest stand forming the upper crown cover.

 P

palm
Member of the Aracaceae (previously Palmae) family, containing over 200 genera and more than 2700 species, many of them economically important for food, fibre, canes, waxes, wood, thatch, and so forth.

permaculture
'Permanent agriculture'. The design and maintenance of sustainable, ecologically favourable, energy efficient agricultural and horticultural systems. The concept includes not only agroforestry but the integration of organic farming principles and intermediate technology, the use of renewable resources and recycling, the exploitation of biodiversity, conservation and habitat protection,as well as social and institutional well-being. It can be applied to urban as well as rural environments.

pest
In the general sense, an insect pest, fungal or viral pathogen, weed, or avian or mammalian pest (birds, rodents).

pH
A numerical measure of the acidity, or hydrogen ion activity, of a soil. The neutral point is pH 7.0. All pH values below 7.0 are acid and all above are alkaline. A change of one unit in pH value represents a tenfold change in hydrogen-ion concentration. pH represents the `intensity' of acidity, not the total exchangeable hydrogen or 'quantity' of potential acidity.

plant nursery
A specially prepared site for germinating seeds and looking after seedlings and young plants under conditions favourable for their growth and development. Facilities for vegetative propagation are also often present.

plant population
The number of plants per unit area. Sometimes referred to as 'plant density 'or 'planting density'.

pollarding
Cutting back in more or less systematic fashion the crown of a tree but leaving a main trunk to 1.5 m or so, with the object of harvesting small wood and browse, of producing regrowth beyond the reach of animals or of reducing the shade cast by the crown.

practice
In agroforestry, a particular use of land involving woody and non-woody plants in some spatial (simultaneous) or temporal (sequential) arrangement. For example, hedgerow, intercropping, homegardens, shifting cultivation. Sometimes referred to as an agroforestry 'technology'. An'agroforestry system' is a specific example of a practice.

propagate
To increase the number of a given plant type. Propagation can be by seed, root sucker, stool, stump, root, stem or leaf cutting, grafting, layering or by micropropagation.

provenance
The place in which any stand of trees is growing. The stand may be indigenous or non-indigenous.

pruning
1. The process of cutting back growth of plants, including roots, but more particularly, side branches of trees, or the sides and tops of hedges.
2. General term to describe the removal by cutting of buds, stems, or entire branches.

 R

rainforest
Generally, a forest that grows in a region of heavy annual precipitation. There are both tropical and temperate rainforests.

rattan
A climbing palm (mainly Calamus spp and others in the lepidocaryoid line). Used for making baskets and furniture.

resin
A thick, sticky liquid that comes out of certain trees and later becomes hard. Acacia senegal produces one of the more valuable resins ('gum arabic'), as do Boswellia and Combretum species.

ring-barking
A method of killing trees by removing a ring (strip) of bark right down to, and including, the cambium. Usually done near the bottom of the trunk.

riverine
A long permanent and semi-permanent stream. It creates a different environment because of the increase in soil moisture. This is termed a riverine environment.

roundwood
Timber or fuelwood prepared in the round state, that is, from felled trees to material trimmed, barked and cross-cut. Logs, transmission poles, pit props and the like are 'round timber'; with fuelwood included, the term is 'roundwood'.

 S

sapling
1. Begins with the end of the seedling stage and ends when trees reach 10 cm diameter at breast height (dbh), the crowns are well elevated, and usually many of the lower branches have died.
2. A loose term for a young tree no longer a seedling but not yet a pole, that is, a few metres high and 2–3 cm in diameter at breast height (dbh), growing vigorously and without dead bark or more than an occasional dead branch.
3. A young tree, large enough to be above goat height, but still immature and not producing fruit.

sapwood
The outer part of the wood of a trunk, in which the sap flows

savanna
A grassland with scattered trees, either as individuals or clumps. Often a transitional type between true grassland and forest. Sometimes spelled 'savannah'.

saw timber
Trees of a size and quality suitable for sawing into timber. Begins at end of the 'pole' stage when height growth falls off and the period of maximum diameter growth begins. Terminates when trees become overmature and die or are cut.

scrub
A vegetation type that is intermediate between forest, bushland and thicket. It implies a poorly productive area.

seedling
A young plant arising from a germinated seed. Trees progress to the sapling stage. A plant grown as a seedling may retain its taproot, unlike one propagated from a cutting, and hence has a differently structured root system.

seed orchard
A tree plantation established primarily for the production of seed of proven genetic quality.

shade-bearing tree
Tree species that will regenerate in shade so is often large seeded. Also known as 'climax species'.

shelterbelt
An extended windbreak of living trees and shrubs established and maintained for the protection of farmlands over an area larger than a single farm.

shifting cultivation
Found mainly in the tropics, especially in humid and sub humid regions. There are different kinds; for example, where a settlement is permanent, but certain fields are fallowed and cropped alternately ('rotational agriculture'). In others, whole settlements move and clear new land once the old is no longer productive. Also called 'swidden' (Old English for a 'burnt clearing'), used more to designate the social group, or 'slash-and-burn', so-called because of the operations undergone.

shrub
1. A woody plant that remains low and produces shoots or trunks from the base; not treelike nor with a single bole. A descriptive term not subject to strict definition.
2. A woody perennial plant differing from a perennial herb by its persistent and woody stem, and from a tree by its low stature and habit of branching from the base.

silviculture
A branch of forestry that is concerned with the methods of raising and growing trees.

silvopastoral system
Any agroforestry system that include trees or shrubs and pastures and animals.

silvopisciculture
Growing trees as part of a fish-farming enterprise.

slash
In forestry, the vegetation (branches and other woody and leafy debris) left on the forest floor after trees have been felled or trimmed.

slash-and-burn system
1. A kind of shifting cultivation in high rainfall areas where the cropping period is followed by a fallow period during which grass, herb, bush or tree growth occurs.
2. A pattern of agriculture in which existing vegetation is cut, stacked and burned to provide space and nutrients for cropping; also called 'swidden' cultivation and shifting cultivation.

slashing
In forestry, cutting back the less tough, competing vegetation, for example, ground cover like bracken. A form of clearing.

smallholder
Usually a farmer who is relatively resource poor, who cultivates or keeps animals, or both, on only a small piece of land, sometimes only a small plot. These farmers may or may not have access to other common land.

softwood
A term used in the timber trade to describe the wood of most conifers (gymnosperms), as distinct from the hardwood, broadleaved species (angiosperms).

stand
In forestry, a community of trees possessing sufficient uniformity of composition, constitution, age, spatial arrangement or condition to be distinguishable from adjacent communities, so forming a silvicultural or management entity.

subsistence farming
Growing crops and, where appropriate, keeping animals so as to provide food (cereals, pulses, vegetable and fruits), shelter materials, and possibly other products (fibres, medicinals) for family use.

sustainable development
The management and conservation of the natural base, and the orientation of technological and institutional change, in such a manner as to ensure the attainment and continued satisfaction of human needs for present and future generations. It conserves land, water, plant and animal genetic resources, is environmentally non-degrading, technically appropriate, economically feasible and socially acceptable.

sustainable land use
Land use that achieves production sufficient to meet the needs of present and future populations while conserving or enhancing the land resources on which that production depends.

sustained yield
In forestry, the annual volume of wood products that a forest can produce continuously under a given system.

sylvopastoral system
An agroforestry land-use system for the concurrent production of trees and animals that graze or browse or both.

 T

taungya system
Method of raising forest trees in combination with (seasonal) agricultural crops. Used in the early stages of establishing a forest plantation. It not only provides some food but also can lessen the establishment costs.

terrace
A broad surface running along the contour. It can be a natural phenomenon or specially constructed to intercept runoff, thereby preventing erosion or conserving moisture. Terraces are sometimes built to provide adequate rooting depths for plants.

thicket
1. A number of trees or shrubs growing close together.
2. A closed stand of bushes and climbers between 3 and 7 metres tall.

thinning
Removal of some of the plants from a crop, or immature trees from a forest, to improve growth of the remainder.

timber
The wood product of a tree obtained by sawing and milling. Timber is a major product of forests.

transplant
1. A plant that has undergone the process of transplanting, as differentiated from a seedling or cutting, which has not. In a forest nursery, seedlings are normally transplanted after one or two years in the seedbed so as to develop a better root system and a sturdier plant.
2. To take a tree or plant from one location and plant it in another. Transplanting happens in many forms: with seedlings in pots, with open-rooted seedlings, balled-root seedlings and with stumps.

tree
1. A woody plant that produces one main trunk or bole and a more or less distinct and elevated head.
2. A woody plant having one well-defined stem and a more or less definitely formed crown and roots, usually attaining a height of at least 2½ metres.

 U

underwood
A tree crop growing beneath the main canopy and forming a distinct lower storey. It is usually of coppice but can be of planted or naturally seeded trees.

 V

vegetative
Not flowering. The stage of development when a plant is producing only roots, stems and leaves, that is, the vegetative organs.

village forest garden
Larger than the homegarden, less densely planted and not so well tended. Planted with higher trees and often containing spontaneous species of herbs or lianas.

 W

watershed
1. A physiographic unit in the landscape defined by the drainage dividers around the area drained by a particular body of water. If a lake, there is often one watershed with subunits for contributing streams. If a river, it may be defined for any point or all.
2. The whole surface drainage area that contributes water to a lake. The total area above a given point on a stream that contributes water to the flow at that point (syn: 'drainage basin', 'catchment basin', 'river basin').
3. The total area, regardless of size, above a given point on a waterway that contributes runoff water to the flow at that point. A major drain-area subdivision of a drainage basin on the basis of this concept.

wilding
A young seedling that develops in the wild without the help of humans. This type of seedling is the best source of stock for some species.

windbreak
A group of trees or shrubs in any arrangement that will afford protection from high winds to animals or crops or both. When the arrangement is in a long line the group is called a shelterbelt. If an associated reason is also to harvest timber at some future date it is sometimes called a 'timberbelt'.

woodland
An open stand of trees > 8 metres high and with a canopy cover of 40% or more, usually among grasses. Woodland is often described by its dominant species, for example, 'Acacia woodland', 'Acacia-Themeda woodland', 'Combretum woodland'.

woodlot
A small plot of trees grown for fuelwood, which can also provide small timber and poles.

 

 Y

 

yield
Plant part harvested and the quantity of it. In agriculture, necessarily related to a specified crop or crops or to a group of animals or to an area, and to a period of time. For multipurpose trees, the amount of each specified part harvested.

 

 Z

zero-grazing
A method of keeping animals that involves bringing fodder to them rather than letting the animals graze freely. It is commonly done where land is in short supply. Napier grass (Pennisetum purpureum) is a common element in zero-grazing systems in East Africa, for example. Trees that can be lopped, like Leuceana leucocephala, provide an important addition to these systems. So too do trees like Acacia tortilis, which produces edible pods.