Tree-related Glossary

Afforestation

The process of converting unforested land to forestry plantations.

Agroforestry

The growing of trees on land also used for crops or livestock.

Ancient woodland

A site that has been wooded continuously since at least AD1600.

Arboretum

Place where trees or shrubs are grown for their scientific or educational interest.

Arboriculture

The cultivation of trees and shrubs for ornamental, landscape or other objectives other than for timber production.

Bare-root tree

Tree lifted for planting without soil or compost around its roots.

Bast

Thin layer of tissue between the bark and the cambium, which carries leaf-sap downwards to the roots.

Beating up

Replacing failed plants after tree planting.

Bole

The stem or trunk of a tree.

Bolling

The permanent trunk of a pollard.

Branch bark ridge

A layer of compacted xylem tissue and wrinkled bark that forms a ridge in the angle where a branch and trunk meet, and serves as a natural protection boundary that resists decay.

Branch collar

A collar of tissue that forms around the base of a branch in some species, usually as the tree ages. With the branch bark ridge, this is one of the tree’s main protection boundaries against decay.

Brash

(n) Small branches trimmed from the sides and top of a main stem.
(v) To cut away the side branches of conifers to c.2m (6’) to improve access or for fire protection.

Broadleaved trees

Deciduous and evergreen dicotyledon trees.

Bryophytes

Mosses and liverworts.

Buttress

Reinforcing projection near the base of the tree.

Callusing

The growth of new tissue across a wound (eg from pruning), which derives from living cells at the edge, and can protect the tree from bacterial and fungal decay.

Cambium

A layer of cellular tissue beneath the bark, in which the growth of bark and wood takes place.

Canker

On a branch or stem, a dead area which has been caused by bacterial or fungal attack.

Canopy

The uppermost layer of woodland structure, usually from 8-30m (25-100’) above the ground. Includes the standard, emergent and understorey trees.

Chitted seed

Seed in which the radicle, or that part of the embryo which develops into the primary root, has just emerged.

Clone

A strain propagated vegetatively from a single individual.

Community Forest

12 urban areas in England designated by the Countryside Agency, where woodland creation and management is being encouraged, to deliver economic, social and enviromental benefits to local communities.

Coppice

(n) A deciduous broadleaved wood which is cut to the ground at regular intervals to produce many shoots from each stool. Also known as a copse.
(v) To cut the shoots from a stool, from which more will grow.

Coppice with standards

A two-storey wood in which standard trees are grown among the coppice or underwood.

Cord

(n) Stack of wood, normally 8 x 4 x 4ft (2.7 x 1.2 x 1.2m), cut from the branches of trees and typically used for firewood or charcoal production.
(v) To cut wood in appropriate lengths and stack in a cord.

Cordwood

Branches suitable for cutting into lengths equal to the cord width.

Coupe

A coppice plot cut on a regular basis, or a clear-felled area in a plantation. Also known as a panel.

Covert

A small wood, usually in the midst of farmland, managed primarily for game.

Crown

The spreading branches and foliage of a tree.

Cultivar

A cultivated variety, or sub-division, of a species, consisting of plants which differ in some way from the norm for that species.

Cutting

A small section of young shoot or root used to propagate a new plant.

Danger zone

The area within two tree lengths, in any direction, of a tree being felled.

Drip line

The ground below the outermost branches of a tree’s crown, where most of the feeding roots are concentrated.

Emergent tree

A tree, the crown of which overtops other standards in the woodland canopy.

Feathered tree

A nursery stock tree with lateral shoots to near ground level.

Field layer

That part of the woodland structure containing herbaceous plants and undershrubs.

Flush

The first spurt of growth after winter when the buds break.

Forest

Originally a term for an area of land, not necessarily wooded, which was controlled by the Crown for deer-hunting. Forest Law applied in these areas. Now generally used to describe a large area of woodland, particularly plantations of coniferous trees, such as those managed by the Forestry Commission. See also Community Forests.

Formative pruning

The pruning of a young plant to achieve a desired shape.

Ground layer

That part of the woodland structure, up to about 10cm (4in) above ground, which contains bryophytes and the seedlings of plants of the higher layers.

Habitat

The place where an organism lives.

Hardwood

The timber of broadleaved trees.

Heartwood

The inner wood of larger branches and trunks, which no longer carries sap.

Hectare

A metric unit of area, 100 x 100m. Comprises 100 ares, each 10 x 10m. There are 2.47 acres to the hectare.

Heeling-in

Temporarily storing transplants or planting stock in a trench backfilled with earth.

High forest

Woodland dominated by full-grown trees suitable for timber.

Honeydew

Sticky substance produced by aphids, which can cause nuisance when it drips onto anything below.

Kerf

The cut made by a saw.

Layer

(n) A side shoot which roots to form a new but connected plant where it touches the ground. (v) To bend over and peg down a shoot so that it will take root.

Leader

The main top shoot of a tree.

Lop and top

See brash

Mast year

A year in which trees produce exceptionally large quantities of seed and fruit.

Mulching

The application of a suitable material to the surface of the soil to conserve moisture, stabilise soil temperature and suppress weed growth.

Mycorrhiza

A symbiosis between soil fungi and the roots of plants

Natural colonisation

The natural spread of trees by seed or suckers into unpreviously wooded ground.

Natural regeneration

The natural replacement or spread of trees by seed or suckers in already wooded ground.

Node

A swelling on a shoot which marks the position of a resting bud.

Nurse species

Hardy, quick-growing trees planted and managed for the purpose of sheltering less vigorous, less robust or more valuable tree species when they are young.

Orthodox seed

Tree seed which can be partially dried and stored.

Park

Originally, land enclosed for the keeping of semi-wild animals. Later, a rural or urban area
managed for amenity.

Pasture-woodland

Woodland in which grazing and browsing by animals is an important influence.

Pioneer species

A tree or shrub species capable of first colonising open ground, before other slower-growing species can become established.

Plantation

An area of woodland or forest consisting mainly of trees planted for timber.

Planting year

The year in which a planted tree crop first grew. For example, trees planted in autumn 00 or spring 01 would both be recorded as 01.

Pole stage

The stage between the thicket stage and maturity, when the young trees resemble poles. For broadleaves, this is from first thinning to about 50 years.

Pollard

A tree which is cut at 2-4m (6-12ft) above ground level, then left to grow again to produce a crop of branches. (v) To cut the branches from such a tree so that they will regrow.

Primary woodland

Woodland that has had a continuous cover of native trees throughout its history.

Provenance

The place of origin of a tree stock, which remains the same no matter where later generations of the tree are raised.

Pruning

Cutting branches from a standing tree.

Recalcitrant seed

Tree seed which cannot be partially dried for storage.

Recent woodland

Woodland which has grown up since the year 1600AD.

Respace

To cut out surplus young trees before they have reached the thinning stage. Refers in
particular to naturally regenerated trees.

Ride

A permanent unsurfaced route within a woodland, used for access, demarcation, extraction of timber and shooting purposes.

Ring-barking

Damage to a tree due to the bark being removed from around the entire circumference of the stem.

Root collar

The base of the stem, where it joins the root.

Root/shoot ratio

The ratio of root growth to the branches and other aerial parts of a plant.

Rotation

The number of years from planting to felling of a tree crop; the length of time between successive cuttings of a coppice plot.

Sapwood

Wood which carries sap. In a young stem, this may be all of the wood; in a larger, older tree or branch, the outermost layer.

Scarifying

Disturbing the soil surface, typically to encourage germination of tree seed.

Screefing

Scraping away the surface vegetation prior to planting, to reduce initial weed competition.

Scrub

In ecology, an area dominated byshrubs, sometimes as a stage in succession to high forest. In forestry, an area of unproductive woodland.

Secondary woodland

Woodland growing on a site that has been cleared at some point in time.

Seedling

Refers to a plant raised from seed (rather than from vegetative propagation) while it remains in its original seedbed. After planting elsewhere, it is known as a transplant.

Semi-natural woodland

On ancient sites, woods made up mainly of native species growing where their presence is
apparently natural and which have not obviously been planted. On recent sites, all stands that have originated mainly by natural regeneration.

Sets

Woody shoots of willow and poplar which root easily when inserted into the soil.

Short rotation coppice

A modern management system, using fast growing species such as willow and poplar, planted close together and cut on a three to five year rotation to produce wood chips.

Shrub layer

That part of the woodland structure, from about 2-4.5m (6-15ft) above ground containing shrubs and young growth of canopy trees.

Singling

Cutting out all but one to three stems on a coppice stool so that it will grow into a timber tree. Singled stems are known as ‘stores’, to distinguish them from ‘maiden’ trees, that have never been cut.

Softwood

The timber of a coniferous tree.

Spinney

A small wood or thicket, typically of spiny trees such as hawthorn and blackthorn.

Spot weeding

Weedkilling a spot around each tree, rather than along complete rows.

Stag-headed

Trees with dead branches which protrude from the top of a live crown. Usually the result of old age, but may also result from injury. Also commonly caused by agricultural drainage or other factors lowering the water table.

Stand

A group or area of trees.

Standard

In woodland structure, a tree forming the dominant layer of the canopy. In nursery stock, a tree with 1.8m (6ft) or more of clear stem.

Stem

The living trunk of a shrub or tree.

Stool

The stump or cut base of a shrub or tree from which new shoots grow.

Stooling

A method of propagating coppice in which regrowth from stools is earthed over to root and later cut away for transplanting.

Structure

The pattern and shape of growth within a woodland, such as the height and density of crowns, position and size of glades, and shape and orientation of margin.

Succession

The process by which one community of plants gives way to another in a series from coloniser to climax.

Sucker

A young tree arising from the roots of an older tree.

Thicket stage

Stage after planting and before the pole stage, when young trees have grown up enough to form a dense thicket.

Thinning

Removal of selected trees from a crop to give the remainder more growing space. A tree so
removed.

Timber

The trunks of trees of large enough diameter to be suitable for producing beams and planks
(minimum dimensions 4.5m/12ft length, and 7cm /3in top diameter); a tree with such a trunk; the use made of such a trunk.

Transpiration

The process by which a plant loses some of the water it absorbs, to allow further absorption by the roots.

Transplant

Small tree less than 120cm (4ft) in height, which has been moved from one nursery bed to another to improve the development of the root system.

Treeshelter

A translucent plastic tube for newly planted trees that encourages faster growth, and guards against predators.

Undercut

In the nursery – an undercut tree is one which has had its roots severed to improve development without transplanting. In felling – a cut made in the front of a tree to reduce the chance of splitting when felling.

Understorey tree

A tree, the crown of which is below that of the dominant trees in the canopy.

Underwood

Wood, whether growing or cut, or coppice poles, young suckers or occasionally, pollard poles.

Viable seed

Seed which is capable of germinating.

Whip

A transplant under about 100cm (3ft) high.

Windblow/windthrow

Trees uprooted either partially or wholly by the wind.

Wood

The part of the stem, inside the cambium, which support the tree, carries water to the crown and stores reserves of food over the winter. Also poles and branches of smaller diameter than timber.

Wood pasture

An area of scattered trees in grassland on which farm animals or deer graze.

Xylem

The woody vascular tissue of a plant which conducts water and mineral salts in the stems, roots and leaves, and supports the softer tissues.