How to prune a young rowan tree
formative pruning / RHS Gardening
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While many trees will naturally form their adult shape as they grow, others need a little assistance to create a clear trunk and a well-spaced canopy of branches. It is wise to keep an eye on young trees and carry out formative pruning as required.
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Good pruning in the early years results in better shaped trees. Image: Tim Sandall/RHS
Suitable for: Young trees, from one year old
Timing: Variable, but often in winter for deciduous trees and spring for evergreens
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- When to carry out formative pruning of trees
- How to carry out formative pruning of trees
This technique is suitable for young trees, from one-year-old until their formative pruning is completed after about four to five years. Most trees sold in garden centres will already be at least partially trained.
One-year-old trees are called ‘maidens’ and are sold as feathered or un-feathered.
Feathered maidens: are sold with their sideshoots attached. On these plants, the side shoots have been kept on and will form the main branches. These trees may be more expensive than un-feathered maidens.
Un-feathered maidens: are sold without their sideshoots, as a single stem. They are often cheaper than feathered maidens, and almost as satisfactory.
When to carry out formative pruning of trees
Pruning of deciduous trees (those that lose their leaves in winter) is often best carried out in winter, as it is easier to see the branch structure.
Pruning of evergreen trees is often carried out in April, as they come into growth.
Exceptions to these rules include tender deciduous trees, best pruned in spring, once the risk of frost has passed, and also stone fruit trees (cherries, flowering cherries, apricots, peaches, plums and nectarines). These can be pruned in winter while young, but are later best pruned in summer. They can be at risk of catching the diseases silver leaf and bacterial canker if large branches, those thicker than your wrist, are pruned in autumn or winter.
How to carry out formative pruning of trees
Most ornamental trees are trained in a central-leader standard, with a clear trunk and a head, or canopy, of branches.
Forming a central-leader standard tree
Young trees can be trained to grow as standards with a 1-2m (3¼-6½ft) trunk.
Where trees grow with a clear central-leading branch that grows upwards ahead of the other branches, it is important not to cut this central leader, as this could spoil the final shape of the tree.
- Remove all side branches from the lower third of the main stem
- Shorten by half all the sideshoots on the middle third of the main stem
- Leave the sideshoots on the top third of the main stem unpruned, apart from the removal of dead, diseased or damaged growth
- Cut to outward facing buds, so that the resulting growth extends outwards rather than into the centre of the tree
- Remove completely the sideshoots that were shortened by half in year one (which should be now be in the lower third of the tree)
- Shorten by half the sideshoots on the middle third of the tree
- Remove any crossing or misplaced branches in the upper third of the tree
Follow the same steps as for year two.
Years four and five
- Clear the trunk of side branches to the height desired
- Continue to remove any crossing, dead, diseased or misplaced branches from the canopy
Then proceed as for a mature specimen, following the advice for the tree in question from a book such as: RHS Pruning & Training by Christopher Brickell and David Joyce, available to buy online from the RHS Book Shop.
Growing a central-leader standard as a branched-head standard to control its size
Some trees, oaks for example, develop as central-leader standards while they are young, but then lose their leader naturally after a number of years, and develop as branched-head standards.
It is possible to reduce the final height of trees that would otherwise grow as central-leader standards by removing the leader and pruning as a branched-head standard.
It is advisable to check in a book first as to whether this technique is suitable for the tree in question, as some trees can be spoiled in shape by premature removal of the leader.
Years one to three
Follow the steps above as for a central-leader standard.
- Remove the leading shoot, cutting to an uppermost strong sideshoot
- Leave three or four sideshoots in the top third of the tree unpruned to form the branches of the branched-head canopy. Only remove any badly placed branches or those that are crossing or rubbing
- Shorten the sideshoots on the middle third of the tree by two-thirds, leaving stubs that can form replacement branches if needed
- Remove all sideshoots from the lower third of the tree, to start creating a clear trunk
- Remove any strongly upward-growing branches that threaten to dominate the canopy
- Remove any crossing or rubbing branches
- Shorten the canopy branches and sideshoots a little to balance the shape. Cut to an outward facing bud to encourage open growth
- Clear the desired height of trunk of any growth. If new growth is stimulated from the trunk by this pruning, rub off the shoots as soon as they emerge
Where upright shoots threaten to compete with the leader of a central-leader standard tree, then a single leading shoot will have to be selected, and the others removed. Choose one that is upright and in line with rest of the tree.
Where the leader is broken by wind, snow or accidental damage, then cut it back to a strong side shoot that is growing fairly vertically. Attach a cane to this side shoot and tie the shoot in to the cane as it extends, training it upwards as a new leader.
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Rowan Tree – Tree Works
All you need to know about the rowan tree, from tips on how to identify it, to typical characteristics; how to spot common diseases and pests and the best way to maintain a rowan tree.
The rowan tree is a UK native species. Also known as the mountain ash because it is able to survive high altitudes, and also because its pinnate leaves are very similar to those of the common ash, this tree is well known for its stunning white spring flowers followed by striking bursts of bright red berries in late summer to early autumn. It’s a deciduous tree known to grow up to 15 metres in height and to live up to 200 years.
The rowan tree has a few other alternative names including witch wiggin, keirn and cuirn.
Witch wiggin as a name derives from the fact the rowan tree used to be planted by homeowners to protect against witches. In Ireland it was grown specifically to ward off evil spirits, and in Wales the rowan tree would regularly be seen in churchyards. In Scotland, it was forbidden to fell a rowan tree.
|Latin name||Sorbus aucuparia|
|Location||UK native, Europe; Asia|
|Lifespan||Up to 200 years|
|Height||Up to 15 metres|
|Appearance||An upright deciduous tree with silvery-grey, smooth bark and purple, hairy leaf buds.|
|Leaves||Leaves are pinnate and turn from green to yellow in autumn. There are 5-8 pairs of long, oval serrated leaflets together with one terminal leaflet at the end.|
|Flowers||Rowan flowers appear in dense clusters with each presenting five creamy white petals.|
|Fruit||Rowan fruits are prominent, scarlet berries that appear in late summer to early autumn.|
|Found in||Streets and gardens|
|Ideal soil||Well drained loam or sand|
|Soil pH||Neutral, acid|
|Aspect||North, south, east or west facing|
|Exposure||Full sun to partial shade; Sheltered or exposed|
|Pests||Aphids, blister mites, sawflies|
|Diseases||Fireblight, silver leaf disease|
Rowan Trees and Wildlife
Moth caterpillars are particularly partial to rowan leaves, especially the autumn green carpet moth and the Welsh wave moth. Apple fruit moth caterpillars enjoy rowan berries, as do numerous birds including the blackbird, the mistle and song thrush, the redstart, redwing, waxwing and fieldfare. The flowers of the tree are rich in pollen and nectar, so attractive to bees and other pollinating insects.
Rowan Tree Symbolism and History
Years ago, rowan trees were often planted by householders to protect against witches. The bright scarlet red berries were considered effective in fighting evil, which is why this tree has long been associated with witches and magic. The Celtic name for the rowan tree is ‘fid na ndruad’, meaning ‘wizards’ tree’. People would often use rowan wood to stir milk to prevent it curdling, and it was also used to make divining rods.
The Importance of Rowan Trees
The pale, yellowy-brown wood of the rowan tree with its distinctive deep-brown heartwood is sometimes used in furniture making, wood-crafting and engraving. The rowan tree is a popular street tree, and its berries are edible and rich in vitamin C, sometimes used to make savoury jellies as meat accompaniments.
Caring for a Rowan Tree
Because the fruit of the rowan tree grows in abundance, it will often weigh heavy on the branches. This makes it essential to carry out regular rowan tree pruning so that there is a robust framework to support the fruit. Otherwise branches are likely to break off, presenting hazards and posing a risk to the health of the tree.
Regular pruning will promote good health by allowing air and sunlight to penetrate as well as letting wind to pass through without barriers, so preventing storm damage. It’s also good to remove crossing or damaged branches so that a clear trunk is left.
Never prune a rowan tree during the growing season because the sap will attract bugs and diseases. Autumn to early winter is considered the most appropriate time for rowan tree pruning, although any time of year is acceptable for dead wood removal.
For more about Rowan tree pruning, follow this link.
If you have a rowan tree that would benefit from expert care and attention, why not get in touch with Tree Works? As fully qualified and highly experienced tree surgeons, we can offer detailed skill and knowledge across all areas of rowan tree care. For a free, no-obligation quotation, call us on 07781 416 354 or get in touch here.
plant pruning rules. Practical recommendations
Many gardeners who do not have the practice of growing mountain ash have doubts about the need to trim the tree, because there are many clear examples that mountain ash can grow and bear fruit without anyone's participation. It should be noted that mountain ash is also a fruit tree and it needs pruning to increase the yield of berries. And if the mountain ash is grown exclusively for decorative purposes, then a beautifully shaped tree will only decorate the garden plot.
In addition, timely and correct pruning of mountain ash is the prevention of diseases that have such consequences as reducing the yield and decorativeness of the tree.
Timing of pruning.
Depending on the age of the tree, as well as the purpose of pruning, the timing of pruning is also different.
So, it is advised to prune young mountain ash immediately after planting, first of all it is important for crown formation.
Mature trees are best pruned during the summer season. In this case, the cuts made are tightened much faster, which reduces the risk of mountain ash infection with various viruses, infections that affect wood tissue and tree bark. Practicing gardeners also note the greater effectiveness of summer tree pruning than when it is carried out in the spring.
Experts advise pruning mountain ash in good weather, on a warm and dry day, because there is a high probability of avoiding fungal infections on the tree, which spread quite quickly in high humidity conditions.
After trimming, the sections must be treated immediately with garden pitch or water-based paint. Some gardeners additionally apply fungicide solutions to the sections. If the cut is not processed, it is fraught with infection with various infections, which can subsequently provoke necrosis of the tree and its death. In order for the cut to tighten faster, it is important that it is even and smooth.
Most often, the following scheme is used for pruning mountain ash. The lower tier of branches is cut so that the height of the trunk is 30 - 60 cm. Pruning is carried out on a ring, that is, almost to the base, or rather, to the annular influx. If necessary, skeletal branches are cut, subordinating them to the conductor and equalizing with other branches. The central conductor of the tree should rise 25-30 cm above the upper tier of branches.
Annual pruning of a tree involves cutting off unnecessary shoots, young shoots, removing old branches that no longer bear fruit, but only hinder the development of the tree by taking food.
In the autumn season, mountain ash requires more care, which involves the adoption of preventive measures to prevent diseases, as well as aimed at increasing the yield in the next season. Rowan, like most trees, grows more actively in spring, and in summer its growth slows down a bit. Starting from September, the mountain ash gradually sinks into a state of dormancy, which finally comes in November. In autumn, it is not recommended to fertilize mountain ash with nitrogen-containing fertilizers, since their action is aimed at the growth of green mass, and this is useless before the start of the dormant period. During this period, pruning of mountain ash is also not desirable, since such a procedure will also contribute to the growth and development of the tree. In addition, the cuts made during the autumn pruning do not have time to heal quickly, and the tree may freeze.
When the winter is warm and severe cold is no longer expected, you can start pruning mountain ash in February. However, in this case, it will be very moderate and gentle. Two or four year old trees can be subjected to such pruning. Pruning of younger as well as older trees is best left at the end of spring - the beginning of summer. In a number of regions, towards the end of winter, they also start pruning other fruit trees, such as apple, pear, and after a while pruning apricot, plum and peach.
Some varieties of mountain ash are very vulnerable to various diseases, so they are recommended to be pruned only in summer.
Rules and methods for pruning mountain ash.
The intensity of pruning a tree, of course, is due to its age.
So, a young tree, after planting, is immediately thinned out quite strongly, paying special attention to those shoots that grow at an acute angle. It is necessary to do this in the first season, because, during the season, they will stretch out, and will create inconvenience in the formation of the crown. In addition, branches arranged in this way can easily break under the weight of the berries, injuring the mountain ash and slowing down its development.
Before proceeding with pruning, the mountain ash is inspected, choosing the highest and thickest branch - it will be the central conductor. Pruning of lateral shoots is carried out so that from one to three buds remain on them. These shoots will begin to grow actively next spring. It is also necessary to remove all small branches, processes located on the trunk.
It should be noted that pruning only a planted tree also allows you to restore the balance between its roots and the above-ground part. So, when digging up a seedling, its roots are injured, respectively, a decrease in the volume of the crown, by trimming it, also reduces the load on the damaged root system. As a result, the plant takes root faster and begins to actively grow.
In the future, for three or four years, pruning of a young tree will be moderate. So, it will be necessary to cut out new shoots located close to the ground, branches that grow inside the crown, as well as shoots affected by diseases or pests. It is important not to rush to trim branches that develop parallel to the central conductor. In some cases, they develop and grow faster, therefore, they can be left in case the center conductor needs to be replaced.
Intensive pruning of a young tree is also not carried out for the reason that it entails a decrease in the number of flower buds, and, consequently, a low yield of the tree.
Some growers prefer to delay pruning young trees in order to produce berries. This is possible when the plant is planted in fertile soil and its moderate moisture is provided. Branches growing at an acute angle should not be cut, they are carefully bent and fixed in position. As a result, a crop from a two-year-old seedling can be harvested the very next year after planting.
Pruning a mature tree over five years old is more labor intensive. In order to rejuvenate the tree, side branches are removed, those that have ceased to bear fruit, or bring an insignificant harvest. Old branches are shortened significantly - by a meter and a half, thus stimulating the emergence of new young shoots. Such pruning should be subjected to no more than a third of the old branches, otherwise it will negatively affect the yield of the tree. Also, branches that are more than four years old are completely cut off.
Start pruning mature trees from the largest and thickest crown branches. Removing them will also contribute to uniform illumination of the entire tree. If there is a need to reduce the height of the crown, its upper part can be cut off. Some gardeners prune the top of the crown every year, since it is much easier to provide care, as well as picking berries from a low tree.
After removing large branches, start trimming small branches. Cut branches growing inside the crown, intersecting, located close to each other.
After such pruning of the crown, the mountain ash will noticeably thin out. However, over the summer period, the tree will quickly gain green mass and restore its decorative appearance.
Increasingly popular among gardeners is gaining such a method of tree formation as pruning rowan on the principle of a dwarf pyramid. As a result of such pruning, the crown of the tree becomes like a Christmas tree. This method of forming a crown is also called a spindle. It is especially recommended by experts for fruit trees such as pear, apple, plum and cherry. This principle of pruning allows you to reduce the size of the crown and, thereby, place more trees on the site. For this reason, it is very much in demand in industrial horticulture.
Pruning according to this principle is carried out as follows. First, the upper part of the trunk is shortened so that the distance to the upper branches is no more than 40 cm. It is necessary to cut the branch above the kidney, placing the cutting tool diagonally. Then a stem is formed, removing those branches that grow at a height of less than 50 cm from the soil surface. Lateral shoots are shortened by approximately one-fourth. The exception, of course, are branches that have any damage.
Another variant of pruning, also following the dwarf pyramid principle, aims to stimulate the growth of lateral branches. In this case, the distance from the top to the first branch is no more than 20 cm. From the bottom of the trunk, all branches growing at a height of less than 50 cm from the soil are also removed. In order to activate the growth of lateral shoots, the tree is cut at a height of 90 cm from the ground. In late May - early June, pegs are set around the perimeter of the crown. Then, the side branches are set at the right angle and tied to pegs. In order for the branches to quickly form the correct angle, from mid-June until the end of summer, shoots 40-50 cm long and additional weights of 200-300 grams are hung. Formative pruning continues over the next two years.
It should be noted that a tree formed according to this principle has a good yield and can withstand heavy loads.
Mistakes made during trimming.
Among the most common mistakes made when pruning mountain ash, in the first place, one should point out not removing branches that grow at an acute angle. Leaving such shoots is fraught with serious injuries for the tree.
Also, quite often, in addition to the central conductor, several more parallel growing large branches are left. Competing with the main trunk, such branches take a significant amount of nutrition, which negatively affects the growth and development of the tree as a whole. The optimal number of main vertical shoots on a bush should be no more than 3 or 5.
The cut and processing is not always correct. So, the correct cut assumes the presence of a smooth surface. In this case, it is much faster tightened, and, thereby, the likelihood of penetration of pathogenic microorganisms into the wound is reduced. Therefore, for trimming, it is necessary to stock up on various well-sharpened tools. Small branches can be removed with a pruner, larger ones need to be cut with a garden saw or a hacksaw. Very thick and large branches, correctly, first, file from below, and then, finish sawing from above. This method will prevent the formation of chipped bark and bullying of branches.
It is also important that the cut, relative to the roots of the tree, be made at an angle of 45 degrees.
Also, immediately after cutting the branch, it is necessary to process the place of the cut. In addition to garden pitch and paint, special ointments can also be used, for example, Funaben 03 PA. This drug already contains a systemic fungicide in its composition and significantly accelerates the healing of cuts.
Tips for gardeners.
If the mountain ash has stopped growing, then in the spring, before the start of sap flow, the top of the crown should be partially cut off. This pruning will encourage the growth of side branches. In addition, you need to prevent the tree from forming inflorescences and fruits, so that all the nutrients are directed to its growth.
In some cases, regular feeding does not bring the expected effect. This can happen when the tree has a weak root. Experts recommend, if possible, dig up the tree and cut off part of the root. After that, the roots will begin to grow, and a powerful and branched root system will be able to absorb more of the necessary nutrients and elements.
If there is a need, on the contrary, to stop the active growth of a tree, then it is enough to carry out summer pruning of mountain ash.
In spring, pruning of mountain ash, like other fruit trees, is carried out strictly before the start of sap flow and swelling of the buds.
In general, pruning a tree is not difficult. And if mountain ash grows on your site, then this procedure should not be neglected.
After all, in addition to preserving the decorative appearance and increasing the yield of berries, this will prevent other fruit trees from being affected by various diseases and pests.
When neglected, a tree becomes a breeding ground for diseases and pests. Sometimes, it is extremely difficult to get rid of both, and in some, especially advanced cases, it is impossible.
During the annual pruning of a tree, attention is paid to the condition of the trunk, the presence of traces of the presence of pests that settle in the bark and, later, penetrate into the wood, infecting it with pathogenic microorganisms that cause necrosis of the tree. When removing the young shoots, the fallen leaves are also removed along the way, where, in the vast majority of cases, pathogens of various fungal infections “live”.
Not too frequent and labor-intensive tree care will allow you to maintain the health of the orchard, which in return will delight you with a rich harvest.
step-by-step instruction for beginners in pictures
Pruning chokeberry is a necessary measure when caring for this fruit crop. If this is not done, the ornamental bush will not look aesthetically pleasing, and a good harvest cannot be harvested. The fruits will be tied only at the ends of the shoots - the sun's rays will not be able to penetrate into the depths of the shoots. The branches near the trunk begin to rot, and eventually the tree becomes weak and dies.
Shoots bear fruit for 5-6 years, then they should not be left. With good care, the tree retains a yield of 12-14 years. When planted as a hedge, total pruning is replaced by removing too long shoots with secateurs. In this case, they do not wait for autumn - they shorten as they grow.
Young shoots along the edge of a perennial shrub can not be uprooted, but used for propagation.
Pruned chokeberry in autumn and spring, before sap flow or after it stops, but while the shoots are still flexible. Many gardeners, to give the tree the desired shape, prefer April or the end of March, until the buds swell. Cut off the elongated shoots, remove the branches frozen or broken off during the winter. But in this case, the main work is done in the fall. Cut off diseased branches with weathered wood or damaged bark, uproot stumps in the near-stem circle. Wood not covered with bark - especially rotting wood - is a favorite wintering place for pest pupae. They should not create ideal conditions.
To cut chokeberry, it is necessary to sharpen the tools: garden or carpentry saw, secateurs. Dull blades cling to the bark, grind the wood, leave burrs. This increases the risk of contracting infectious diseases. Otherwise, after a while, the branches that were inaccurately shortened will have to be disposed of.
Antiseptics are prepared for the treatment of sections - garden pitch, crushed charcoal (or activated) charcoal, oil paint. When caring for chokeberry in the fall, you can first remove all the branches, and only then disinfect the damaged areas. In case of unscheduled work, open wood is covered immediately, trying not to touch the open wood with your hands.
For beginner gardeners, it is enough to give the chokeberry the correct shape - remove excess shoots and thin out the bush. When growing a green hedge, shorten protruding branches so that they are all the same length, uproot shoots from a common root system that expand the planting.
A step-by-step diagram in pictures of pruning chokeberry in autumn for beginners is as follows: They don’t touch him, don’t pinch the top, even if he stretched out over the summer, they don’t uproot the shoots. The roots of a perennial shrub lie shallow - 50-60 cm, if they are damaged, the whole plant will die.
When forming a hedge, only side shoots are cut as they grow. As already mentioned, not only in the fall, but the whole season. To properly trim the blackberry according to this scheme, you do not need to be an experienced gardener, but to give a fashionable shape to the black rowan, you need to be able to care for the garden. To facilitate the collection of berries and reduce the area required for the growth of a shrub, it is given the shape of a dwarf pyramid. The crown becomes like a Christmas tree.
The tallest central trunk of a three-year-old plant is shortened above the bud with an oblique cut, but so that the next layer of branches is 40 cm lower. . This shape is called a "spindle".
To stimulate the growth of lateral shoots, the pruning scheme of the dwarf pyramid is slightly changed. The main trunk is cut at a height of 0.9-1 m from the ground. Additional shoots and the upper tier of skeletal branches so that they are 20 cm lower. Branches that do not stretch in the right direction are tied to pegs driven in in the trunk circle, bend where required. You can hang weights so that they do not deviate. Formative pruning is carried out as needed.
Dwarf trees are more productive and easier to care for. Access to any part is simplified, the light evenly hits all branches. In addition, as already mentioned, the "pyramids" take up less space.
Types of pruning
It may be interesting
Crown formation methods differ not only in shape, but also in the types of work. After each season, the site is prepared for the next. Remove fallen leaves, dig up the soil. Aronia also needs autumn pruning, which is commonly called sanitary. In first-year seedlings, even if the branches are significantly extended, they are not trimmed so as not to weaken the plant. Remove only damaged, broken shoots, with wet areas and peeled bark. Be sure to take out cut branches and fallen leaves from the near-stem circle, even if a young seedling needs warming for the winter.
Unnecessary stumps are uprooted. Mulch only with dried materials - sawdust, straw, spruce branches, etc. A humid environment creates ideal conditions for the development of fungal spores. A short-term thaw is enough to activate, and in the spring the whole tree will already be infected.
The purpose of shaping pruning depends on the purpose for which the aronia is grown in the garden. In order to collect berries, reduce the height of the bush and remove excess shoots. The scheme is chosen according to one's own taste - traditional or pyramidal. How to cut correctly, you can see on the video. Planted to create a hedge - shorten the shoots as needed. Anti-aging pruning is carried out in autumn in shrubs whose age is considered "critical" - 12-15 years. At this time, the yield drops sharply, the branches become stiff, begin to break off under their own weight.
After stopping the flow of sap, a total cleaning of the trunk is carried out. The top is cut to a height of 1-1.2 meters from the soil level, skeletal branches to a length of 40 cm from the trunk, keeping several growth buds - 3-4 is enough. The necessary shape of the tree is given only next spring, when young shoots grow enough. In this case, the harvest can be harvested only after 1-2 years.
It is possible to rejuvenate chokeberry without loss of yield. To do this, selectively cut off shoots older than 7 years, at the very base (the remaining stumps are uprooted in the fall so that shoots do not appear on them in the spring, thickening the bush). Strong sprouts, 2-3 years old, do not touch. If necessary, they shorten the top.
Recommendations for gardeners
If the seedling was planted independently, then care for it begins with giving the desired shape. In the first year, pruning is not carried out, but shoots growing at an angle must be given the right direction. If it is a shoot, turn and fix on a support. Branches sometimes have to be cut off. All the same, in the future they will prevent the formation of a crown of the desired shape.
Starting the shaping pruning, select the main trunk. This should be the tallest and strongest shoot, or skeletal branch. Trimming the side branches, leave 3-4 buds. The stem (lower part of the trunk) is cleaned annually. When the roots are damaged, the height and volume of the aerial part is reduced. In order for the root system to recover, you need to reduce the load. Branches with damaged bark are cut off at the level of the trunk.
Shoots that develop parallel to the central stem should not be removed. When they grow faster, more fruit ovaries are formed than on the main stem, they are replaced.
If the soil is fertile, the watering regime is set correctly, berries can be harvested already from a two-year-old seedling. In this case, formative pruning can be postponed for 2 years.