Tools used forare numerous and varied and each has been devised for a specific purpose. There are three main groups: Knives, secateurs and saws.
Today the use of knives is limited because few people know how to use them properly, but in the hands of a skilled operator they are still the best pruning tool. There are a number on the market, of differing sizes and patterns. Almost any kind of knife can be used for pruning provided the blade is of good steel, capable of keeping a good edge, and is firmly set into the handle so that it cannot come loose under pressure.
A pruning knife must be sharp; a blunt knife is useless and can also be dangerous. More wounds are inflicted with blunt knives than with sharp ones, because more pressure has to be applied to make them cut and this is when they are likely to slip. When pruning, hold the branch below the point where the cut is to be made. Start with the knife behind the branch, just below the level of the chosen bud. With a slightly upward movement make the cut at an angle, to finish just above the bud.
A knife should be sharpened on an oil-stone. Inspection of the blade will indicate how it was sharpened in the factory: often one side of the blade is flat and the other has been sharpened at an angle, sometimes both have been sharpened at an angle. Where possible sharpen to the same angle as previously. However, some people find it difficult to keep a knife blade at a fixed angle, and they may have to compromise and sharpen both sides flat on the stone.
Keep your pruning knife for just this task. Don’t use it for cutting any old thing or for prizing tacks out of wood or the edge of the blade will soon become chipped – even with constant care this can too easily happen. If the blade does become chipped, grind the edge down until it is again straight and then sharpen in the normal manner. Once a blade has been sharpened a keen edge can be produced and maintained as necessary by rubbing on a razor strop.
Though knives may not be in regular use for pruning there are some jobs for which they have to be used: paring smooth the rind after sawing off a branch; gouging out diseased material from a branch prior to painting with a wound protectant; trimming back young growth that has been damaged by late frosts; and removing twiggy growths along trunks so as not to leave basal buds.
Using secateurs requires little effort and no special skill; they are an indispensable aid to the gardener. There are two main types: the parrot beak with two cutting blades, and the anvil with one.
These are so called because of the shape of the cutting blades. They are available in several sizes, the products of different manufacturers varying slightly in design and size range. One type has a swivel handle which takes wrist fatigue out of the job. These are used in one hand and are capable of cutting stems of up to 1 cm (3/8 in) easily and up to 2 cm (¾ in) with care. Do not try to cut heavier wood with them. When cutting use a straight action and avoid twisting the blades.
After use, remove ingrained dirt with emery paper and before putting away wipe all parts with an oily cloth and put a spot of oil on the pivot and spring. When not actually working with them, keep the catch on and the blades together.
These have an anvil which holds the stem while the single blade does the cutting. They are available in several sizes and with one or two special modifications, (e.g. for cutting wire). They need a little more attention in handling than the previous type. Make the blade do the cutting; do not try to make the anvil push the stem against the cutting edge. Always have the blade where it can be seen and place the blade above the bud when making the cut. Again, do not attempt to cut wood that is too thick, like the parrot-beak type, these will easily cope with wood up to 1 cm (1/2 in), and with care up to 2 cm (3/4 in). Avoid twisting the blades when cutting, as this strains them and causes the blade to cut off-centre, which results in bruising or tearing of the bark. The blade must be sharp at all times and the anvil in good condition.
Long-Handled Secateurs or Loppers
These are modifications of the anvil or parrot-beak type on handles about 45 cm (18 in) long. The blade or blades open wider, and because the handle is longer, there is more leverage and the loppers can cope easily with wood up to 2 cm (3/4 in) and with care up to 2.5 cm (1 in). Two hands are needed to operate them.
Long-Arm or Long-Armed Pruners
These are anvil-type secateurs fixed on the end of a pole which comes in varying lengths, perhaps up to 2.7 m (9 ft). The single cutting blade is operated by a wire attached to a handle. When the handle is in the up position the blade is open; to operate, pull down the handle and this drives the blade on to its anvil. This high-reaching tool also needs two hands, one to hold and one to operate.
Saws take over from secateurs when branches of more than 2.5 cm (1 in) thickness have to be cut. Joiner’s or carpenter’s saws should not be used for pruning; saws manufactured for the job are to be preferred for they stand up better to the rougher work and are easier to insert and use in difficult places.
This type has one cutting edge and has a folding handle. It can deal with wood up to 4 cm (1-1/4 in) in diameter but above this the work becomes tiring. Its main use is to saw awkwardly placed small branches or to remove one branch where several are growing close together and loppers cannot be used.
This is two-edged, with larger teeth on one side than on the other. It is used for branches up to perhaps 8 cm (3 in) in diameter, the initial rougher work being carried out with the larger teeth and the final finishing cut made with the smaller. However, it is unsuitable for dealing with branches growing close together, as damage can be caused by the second cutting edge. After use, remove sawdust from the teeth with a wire brush and wipe with an oily rag.
The curved blade has teeth along one side only. It can be used for the same tasks as the pruning saw and is preferable to it.
Here we have a metal frame with a detachable saw blade which is capable of dealing with all branches as long as there is enough space to operate; replace with a new blade when the old one shows signs of wear.
When sawing off a small branch, take its weight so that it does not break away and tear the bark. If one does not have a free hand or if the branch is large, it should first be undercut until the wood begins to pinch; then remove the saw and start on the top of the branch. Don’t worry about being directly above the lower cut. This does not matter. As the branch parts from the tree it will break cleanly between the two cuts. The stub remaining should then be cut off neatly, finishing just slightly proud of the trunk.
LADDERS AND STEPS
When pruning has to be carried out on trees and even on some large shrubs, some if not all of the branches may be out of reach and a ladder or steps will be necessary. Ensure that these are in good condition and securely placed.
The removal of any part of a plant causes a wound which has to heal. Just below the bark of a shrub or tree is a single, continuous layer of cells known as the cambium. Following a cut, these cells begin to divide, producing callus tissue which forms in a ring around the circumference of the cut and continues to increase inwards for varying distances, depending on the size of cut, age, vigour, condition and kind of tree or shrub. On small young branches, the entire end of the cut may be sealed in this way, but on thicker and older wood healing may not be complete and callus may only form around the edge of the cut.
Roughly cut, broken, torn or bruised wood is slow to heal because the ring of cambium has been broken and a complete seal is rarely possible. Broken branches or those roughly cut with a large-toothed saw, should have the stubs taken off with a finer-toothed saw and the edge of the bark pared smooth with a sharp knife. Where tears have taken place, all the edges of exposed bark should be pared smooth.
The formation of callus tissue prevents the entry of disease organisms, so it is important that this healing process should be as rapid as possible. It is quite fast on young shoots but it can take a long time where old and large branches have been removed. All cuts above 2.5 cm (1 in) should be treated with a wound sealant which provides a protection against disease entry until the healing process is complete. Modern sealants are tar-based bituminous paints. They have an elastic property, which enables the wood surface to stretch and shrink (without cracking), and are waterproof.