A-B   C   D-F   G-J   K-M   N-P   R-S   T-V   W-Z  

R-S

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.

A-B   C   D-F   G-J   K-M   N-P   R-S   T-V   W-Z