Abort: When growth ceases in the early stages of formation
Acidic soil: This is a soil which has an pH of less than 7.
Aerated soil: This is a soil with plenty of air spaces , providing plenty of oxygen for, as an example, good root growth.
Aggregate soil: Where many soil particles are held together in volume, to form a clod.
Alkaline soil: This occurs when the pH of the soil is more than 7 (neutral)
Alternate host: for example when an insect needs more than one plant to complete its life cycle
Amino acids: These are the building blocks of proteins.
Anaerobic soil: A soil where not enough oxygen is present for healthy tree growth.
Anther: The pollen-producing part, at the top of the stamen, to be found in the flower
Anther: The blossom part that produces pollen and bees collect. (Pollination process essential)
Apical buds: These are terminal buds of leading shoots.
Armillaria root rot: a deadly fungus which can affect the roots of many trees and kills the tree.
Artificial manures: another term for commercial inorganic fertilisers.
Availability of nutrients: At different pH levels, some nutrients are more available than others.
Axillary bud: A bud which is found in the axil of a leaf.
Balled roots: These trees are transplanted with the soil around the roots and held together by hessian or plastic wrapping material.
Bare root: When fruit trees are fully dormant, trees can be transplanted, without any soil around the roots
Bark ringing: This is the removal of a partial ring of bark of the tree trunk in order to reduce growth or encourage cropping.
Basal buds: The lowest-placed buds of the shoots or laterals of fruit trees
Basal shoots: Appear at ground level around the trunk of the tree.
Biennial bearing: Indicates that the tree crops very heavily one year, with the following year very little crop
Blind bud: These buds fail to develop into shoots or leaves
Bourse: The swollen part of the stem found at the base of attachment of apples and pear fruits
Bourse bud: either a fruit bud or a wood bud found at the bourse which usually is only 3 to 4 mm in length.
Bracket fungi: fungi which mostly live off the dead wood in the centre/cylinder of the trunk of a tree.
Brown rot: a fungal disease affecting mainly the fruits of trees.
Brutting: the technique of breaking a newly formed shoot during the summer, and leaving it partially attached.
Bud nicking: removing a piece of the bark below the bud, to restrict the bud in growth.
Bud notching: removing a piece of bark above the bud to encourage the bud to develop.
Bud rubbing: rubbing off fruit buds by hand on a section of wood or shoot.
Callussing: These are the cells which the tree uses to heal and close wounds, due to, for example, pruning or rabbit damage to the trunks.
Cambium: The thin layer of growth cells immediately below the bark of the tree.
Canker: A fungal disease affecting the wood of all ages in the tree
Capillary water: the water held in the small pores of the soil
Caterpillars: These are larvae, or the immature stages of various fruit pests
Central leader tree: a tree usually in the shape of a cone, with the tallest shoot as the central leader
Chelated: A special formulation of plant nutrients, which will remain active for some time in alkaline soils
Chelated iron: this is a chemical structure whereby the uptake of iron from the soil is made easier for the plant/tree.
Chlorophyll: These are the compounds in green leaves which manufacture the carbohydrates under the influence of sunlight (photosynthesis)
Chlorosis: a condition in the tree, relating to the failure of chlorophyll to develop. Chlorotic leaves are yellow/white.
Collar Rot: A fungal disease found at the base of fruit trees.
Contact insecticides: These sprays kill insects once contact has been made
Cordon: usually a close-planted tree, in which the side shoots are kept short due to summer and winter pruning.
Cover crop: a close growing crop for the purpose of protecting and improving the soil between trees (grass, clover etc.)
Crotch/Angle: The junction and angle of the main framework branches with the trunk of the tree.
Crown: The overall shape, created by the total volume of the branches of the tree.
Chromosomes: the structure which holds the DNA/RNA amino acids in the nucleus of the cell.
Dard: A short lateral shoot of 7 to 8 cm in length. Closes down early and forms a fruit bud at its end.
Defruiting: The removal of all immature fruits from some branches or the whole tree.
Deblossoming: The removal of blossom from specific areas of the tree.
Die-back: The condition when shoots or branches are losing life, starting at the tips of shoots or end of branches
Diploid: Fruit varieties with two sets of chromosomes
Dormant bud: An inactive bud. In the winter all buds are inactive. During the growing season, some remain dormant.
Dwarf bush tree: This is a 2 year old tree on dwarf or semi dwarf rootstock.
Dwarf pyramid: A tree in which the side branches are kept close to the trunk by means of summer pruning
Drainage: The degree and natural ability of a soil to get rid of surplus water
Erosion: The loss of soil through the action of wind or water
Evaporation: The loss of water/moisture due to different temperature/air pressure gradients
Espalier: A tree suitable for training against a wall or a fence
Established tree: A tree that is at least 4 years old
Fan: A tree form suitable for a wall or a fence, mainly used for plums, cherries and other stone fruits.
Feathers: Shoots grown on the vertical leading shoot on 1 year or 2 year old trees
Fertility: Status of the soil for plants to grow or plants to reproduce.
Fertilisers: Refers mainly to artificial, synthetically produced materials, added to soils for extra nutrition of plants and trees.
Field capacity: The amount of moisture left and held in the soil after drainage has removed the surplus water.
Fixation: When certain elements are locked in the soil due to certain levels of soil acidity (pH)
Flood plain: The land bordering a stream or river, which tends to flood from time to tim
Flower bud: An unopened flower which may lead to a fruit.
Foliar feed: A liquid solution of plant nutrients sprayed onto the foliage of plants and trees
Fork angles: The steepness at which branches are fitted to the main trunk of the tree.
Friable: The condition of a soil when it crumbles easily.
Fruit bud: A bud that will develop into a flower, which in turn may form a fruit.
Fruit thinning: The removal of immature fruits
Fungicides: Manufactured compounds used to control fungal diseases