The Garden pp. 327-238 (October 8, 1892)

ROOT-PRUNING.

There is considerable difference of opinion as to the results obtained from root-pruning, many objecting to what they term mutilation of the roots and advising letting the tree have free play. I believe in root-pruning provided it is done carefully and at the right time. There is no better time than the month of September; the earlier in the month the better for such early fruits as Cherries, Apricots, and Plums. Apples and Pears may be operated on early in October, and not only root-pruned, but in many cases lifted and replanted if necessary. One of the chief objections to root-pruning is that trees left alone, for instance those in orchards, fruit freely without the roots being cut. Such is the case, but then the top is left alone also, so that the top-growth balances the root-growth and the trees are fruitful. If old orchard trees are severely cut in at the top, the next season there is a forest of small twigs and no fruit. Careful thinning may take place, but sufficient wood must be allowed to absorb the supply of food from the roots. Root-pruning in every case would be radically wrong. Where it is required is with trees pruned severely or not allowed to become large, as this cutting in of the top without restricting the roots produces unfruitful trees. This pruning has been practised in orchard and fruit houses for years with success, as fruit trees in pots must be root-pruned at least once in two years to keep them from growing too much and to induce them to bear freely. It is much the same with various fruits. For instance, Figs to be profitable must have a restricted root-run, which is a kind of root-pruning. In many gardens pyramids or bush trees are planted near walks; these are most ornamental in the garden, but in a short time fill the allotted space allowed them. The result is that severe annual pruning is necessary, and every year a strong growth with few fruits is produced. These are the trees that benefit by root-pruning, doing away with the severe top cutting for a time. Of course there are different ways to go to work, as if extreme measures are taken at once the trees are injured; indeed, root-pruning requires a certain amount of skill, and with large old trees with coarse roots only a portion of the roots should be cut, say a third or half, doing the work in two or three seasons instead of one. With small trees there is less danger, provided the cutting takes place at a fair distance from the stem of the trees. Fruit trees, such as pyramids, would often be better if lifted oftener when in a young state, say every two or three years; then root-pruning would be out of the question, as a sturdy growth would result. We see how well trees in nurseries grow with frequent removal, and how late it is often practised, and with no evil results, simply because the roots are a mass of fibre that soon takes to the soil. It is the large coarse roots that succumb to lifting; hence the advantage of root-pruning to induce better root action by the formation of fibrous roots. Of course stocks have much to answer for, as these are not all suited for the scion, but of late more attention has been given to these and to grafting or double-grafting. Apples on the Paradise stock and Pears on the Quince rarely fail to give heavy crops of fruit. The Quince stock fails in some soils; for instance, on chalk or gravel the Pear stock often does best.— G. Wythes.

—This is a very important matter, and should be well considered by all who make hardy fruit culture a study. It is pitiable to see so many fruit trees of all kinds in gardens growing freely and never bearing any fruit, when a few hours' well-conducted labour would make them not only profitable, but also interesting. A properly nursery-prepared tree when sent out will not have a single tap root, presuming, of course, that all nursery trees are frequently moved after they have been grafted. I also presume that nurserymen, in planting their fruit trees as maidens or otherwise, carefully cut the roots. The tap root would in that case be cut off, and I have yet to learn that when once the tap root is severed a few inches from its base a second is made; therefore, I fail to see how the tap root is responsible for all the superfluous growth which some trees make. Many fruit trees, Apples for instance, would not require root-pruning nearly as much as some persons appear to think if the top growth was managed in a more rational manner than is very often the case. The proper manipulation of exuberant shoots will generally bring a tree into fruit-bearing with much less trouble and considerably less check to the tree itself than root-pruning. I am aware that there are instances which do not admit of the branches being managed in the manner I will indicate. In these cases the only remedy to render a tree fruitful is to root-prune with a view to check exuberant top-growth and bring the tree into subjection, so that it will give some return for the space it occupies. The merest novice can determine whether it is necessary to root-prune a tree or not when I say that if space will allow for the branches to extend both in width and height it is not necessary to do this. In the case of pyramid trees growing in a limited space, say beside a path or otherwise, the question is different. The continual pruning of strong shoots into two or three eyes every year without curtailing the run of the fibreless roots only tends to increase the evil. Allow the leading branches to remain with the exception of removing the tip, and the result with most varieties would be the formation the following season of bloom-buds the whole length of the shoot and a reduced growth in the length of shoot. Even the year after the previous practice of hard pruning was abolished, each year afterwards less length of new growth will be produced, but a much larger increased area of fruiting space, and absolutely without touching the roots in the shape of pruning. Standard Apple trees in orchards are living evidence of the utility of this plan of dealing with trees without the necessity of root-pruning. Very seldom indeed do we hear of anyone root-pruning this class of tree; neither is it the plan to annually cut back the shoots, and why should it be done in the case of bushes? Pyramid-trained trees I hold to be totally useless where a full crop of fruit is the first consideration. If Apple tree roots were paid more attention to on the surface than is often the case, we should hear less complaint of trees wanting root-pruning than at present. How often do we see young trees of all shapes carrying good crops of fruit in the kitchen garden with many of the roots quite bare on the surface, and in the driest weather, too, and not the faintest sign of a particle of mulching having been given them with a view to conserving the moisture in the soil? It is not to be wondered at if the roots of such trees descend deeply in quest of that moisture which is denied them in the proper quarter. After a few years of such treatment these same trees are often found making a lot of gross growth and lacking in fruit-production, caused in a great measure also by the annual digging in of manure to the roots during the winter months with a view to making the trees grow well. All these points need some consideration when discussing the great question of root-pruning.
     In planting Apple trees I do not mix manure with the soil, but add a few shovelfuls of vegetable refuse, wood ashes, &c. I, however, sometimes find it absolutely necessary to fork in a quantity of partly decayed manure about the roots the following autumn. In some soils trees will grow fast enough without the aid of manure, except that employed for mulching, but in others even in the same field the growth of the same kinds of Apple trees is as different as possible. The colour of the leaves, too, is quite distinct; instead of the deep green colour and leathery feel of the foliage, a paleness and flimsiness are much too evident. Now it would be folly to allow trees such as these to struggle on without the aid of some food to give them their proper colour and necessary growth. This is an instance where the rule of not manuring trees for a certain number of years after planting must be put on one side, and the circumstances of the case thoroughly taken into consideration. In planting an orchard on a newly-broken-up field instances like this are almost sure to crop up, as seldom indeed can a single field beyond an acre in extent be found of exactly the same kind of soil. Where the newly-planted trees do not make satisfactory progress the first year, it would be folly to allow them to stand still when a dose of manure of some kind would be of great advantage The longer the trees remain in this unsatisfactory state, the longer will they be before they come into bearing. Apple trees, with the exception of standards, if well attended to when first planted ought to bear fruit the second year after the shift. In the case of standards growth is of more importance than fruit. The first two seasons after planting I pick off all bloom buds from the standard trees, and by the increased length of shoot the plan is justifiable.— E.M.

—The value and necessity of root are not understood and recognised in the way should be and few people are aware of the effects it has on trees, especially such as are heavy land and full of gross growth. The reason of this is that they keep running to wood and make timber instead of flower buds; but once check that gross tendency it is easy to restrain after, for Nature then rights herself, and one crop leads on to another. It must be borne in mind, however, that root-pruning must not be carried out in a rough-and-ready fashion, as otherwise harm instead of good will result, for if roots are hacked and mutilated and severed too near to the tree, a long time will elapse before the tree will recover. This being so, great care should be exercised in the operation. The way to set about it is first to open out a trench of a workable width, say 18 inches or so, according to the size of the tree, and if the tree is a large one, the trench ought not to be nearer than 4 feet to the stem, and even then it will be better if it is not carried entirely round. The reason of this is that the check would be too great, and to guard against that, half should be done one year and the other half next. In dealing with the roots, all the small fibrous ones met with should be taken great care of and saved, but all those that are big cut through, but not, of course, with a spade. The proper tool for that purpose is a keen-edged knife, as it is important that the cut be made perfectly smooth, for it is only such wounds that heal freely, others causing a dying back through decay of the parts. With all the roots severed in the way referred to, the next thing is to cover them up as quickly as possible by returning the soil and filling in the trench, and if the soil is close and tenacious, road scrapings will do much good. Not only is root-pruning desirable and beneficial for over robust fruit trees, but it is the proper thing to do by way of preparation for any of an ornamental character, or shrubs of large size that are to be moved. Although root-pruning may be carried out from now on through the winter, it is better to do it early while the leaves are still on, as then the healing process goes on more quickly and fresh fibres are more speedily formed.— S. D.