Fruit tree pruning

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A community apple orchard originally planted for productive use during the 1920s, in Westcliff on Sea (Essex, England), illustrating long neglected trees that have recently been pruned to renew their health and cropping potential Orchard3.jpg
A community apple orchard originally planted for productive use during the 1920s, in Westcliff on Sea (Essex, England), illustrating long neglected trees that have recently been pruned to renew their health and cropping potential

Fruit tree pruning is the cutting and removing of selected parts of a fruit tree. It spans a number of horticultural techniques. Pruning often means cutting branches back, sometimes removing smaller limbs entirely. It may also mean removal of young shoots, buds, and leaves.

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Established orchard practice of both organic and nonorganic types typically includes pruning. Pruning can control growth, remove dead or diseased wood, and stimulate the formation of flowers and fruit buds. It is widely stated that careful attention to pruning and training young trees improves their later productivity and longevity, and that good pruning and training can also prevent later injury from weak crotches or forks (where a tree trunk splits into two or more branches) that break from the weight of fruit, snow, or ice on the branches.

Some sustainable agriculture or permaculture personalities, such as Sepp Holzer and Masanobu Fukuoka, advocate and practice no-pruning methods, which runs counter to the widespread confidence in the idea that pruning produces superior results compared with not pruning. Many books about fruit-growing assert advantages and disadvantages of pruning or not pruning, although without randomized controlled trials, it is hard to separate theorizing and traditional knowledge from evidence-based recommendations.

Overview

An apple tree sprout is being converted to a branched, fruit-bearing spur by an arborist. Numbers show the sequence of cuts, which occurred during two years. Apple spur M D Vaden.jpg
An apple tree sprout is being converted to a branched, fruit-bearing spur by an arborist. Numbers show the sequence of cuts, which occurred during two years.

Plants form new tissue in an area called the meristem, located near the tips of roots and shoots, where active cell division takes place. Meristem growth is aimed at ensuring that leaves are quickly elevated into sunlight, and that roots are able to penetrate deeply into the soil. Once adequate height and length is achieved by the stems and roots, they begin to thicken to support the plant. On the shoots, these growing tips of the plant are called apical buds. The apical meristem (or tip) produces the growth hormone auxin, which not only promotes cell division, but also diffuses downwards and inhibits the development of lateral bud growth that otherwise competes with the apical tip for light and nutrients. Removing the apical tip and its suppressive hormone lets lower, dormant lateral buds develop, and the buds between the leaf stalk and stem produce new shoots that compete to become lead growth.

Manipulating this natural response to damage (known as the principle of apical dominance) by processes such as pruning (as well as coppicing and pollarding) allows the arborist to determine the shape, size, and productivity of many fruiting trees and bushes. The main aim when pruning fruit trees is usually to maximize fruit yield. Unpruned trees tend to produce large numbers of small fruits that may be difficult to reach when harvesting by hand. Branches can become broken by the weight of the crop, and the cropping may become biennial (that is, bearing fruit only every other year). Overpruned trees on the other hand tend to produce light crops of large, flavourless fruit that does not store well. Careful pruning balances shoot growth and fruit production.

One of the simplest instructions given in nearly every article or book chapter on the subject is that no branches should cross each other, that is, rub against each other, and that one of them should be selected and removed.

Formative pruning of bush trees

In the early years of the tree's life, it is important to develop a framework sufficiently strong to bear the weight of crops. This requires formative pruning to reinforce the tree. Formative pruning of apple (Malus pumila) and pear (Pyrus communis) trees should be carried out in the dormant winter months. For the Northern hemisphere, this should occur between November and March; For the Southern hemisphere, June and September. Stone fruits—such as cherries, plums, and gages—have different requirements, and should not be pruned in dormant months.

Maiden tree

A maiden whip (a one-year-old tree with no side shoots) should be pruned to a bud with two buds below it at about 80 cm (31.5 in) from the ground immediately after planting to produce primary branches during the first growing season. A feathered maiden (that is, a one-year-old tree with several side branches) should have its main stem pruned back to three or four strong shoots at 80 cm (31.5 in) from the ground. Side shoots should be shortened by two thirds of their length to an upward or outward facing bud. Lower shoots should be removed flush with the stem.

Two year

Remove lower shoots and prune between three and five of the best-placed shoots by half to an upwards or outwards facing bud to form what becomes the tree's main structural branches. Remove any inward-facing shoots.

Three year

Prune leading shoots of branches selected to extend the framework by half, to a bud facing in the desired direction. Select four good laterals to fill the framework and shorten these by a half. Prune any remaining laterals to four buds to form fruiting spurs.

Four year

The tree has begun to fruit and requires only limited formative pruning. Shorten leaders by one third and prune laterals not required to extend the framework to four buds.

Five year and onwards

The tree is established, and should be pruned annually as described in the following section.

Pruning the cropping tree

Spur pruning Spurpruning.png
Spur pruning

Before pruning, distinguish between spur-bearing varieties, tip-bearing varieties, and an intermediate between the two that bears both on spurs and at the tips. Spur-bearing trees occur more frequently than tip-bearing trees, and they bear most of their fruit yearly at the end of short lateral pieces of wood (spurs) up to about 4 inches long.

Spur-bearing types include apples of the varieties 'Cox's Orange Pippin', 'James Grieve' and 'Sunset', and pears such as 'Conference', 'Doyenne du Commice', and 'Williams Bon Chretien'. Tip-bearers on the other hand produce most of their fruit buds at the tips of slender shoots grown the previous summer, and include the apples 'Worcester Pearmain' and 'Irish Peach', and the pears such as 'Jargonelle' and 'Josephine de Malines'. There are basically three types of pruning that are applied once the main shape of the tree has been established. These are:

Renewal pruning Renewalpruning.png
Renewal pruning

Pruning of tip bearers

Tip-bearers should be pruned lightly in winter using the regulatory system (see above). Any maiden shoots less than 25 cm (9.8 in) in length should be left untouched as they have fruit buds at their tips. Longer shoots are spur pruned to prevent overcrowding and to stimulate the production of more short-tip-bearing shoots the following year. Branch leaders are 'tipped', removing the top three or four buds to a bud facing in the desired direction to make them branch out and so produce more tip-bearing shoots.

See also

Related Research Articles

Fruit tree forms

Fruit trees are grown in a variety of shapes, sometimes to please the eye but mainly to encourage fruit production. The form or shape of fruit trees can be manipulated by pruning and training. Shaping and promoting a particular tree form is done to establish the plant in a particular situation under certain environmental conditions, to increase fruit yield, and to enhance fruit quality. For example, pruning a tree to a pyramid shape enables trees to be planted closer together. An open bowl or cup form helps sunlight penetrate the canopy, thus encouraging a high fruit yield whilst keeping the tree short and accessible for harvesting. Other shapes such as cordons, espaliers and fans offer opportunities for growing trees two dimensionally against walls or fences, or they can be trained to function as barriers.

Pollarding Technique of severe pruning of trees

Pollarding is a pruning system involving the removal of the upper branches of a tree, which promotes the growth of a dense head of foliage and branches. In ancient Rome, Propertius mentioned pollarding during the 1st century BCE. The practice occurred commonly in Europe since medieval times, and takes place today in urban areas worldwide, primarily to maintain trees at a determined height or to place new shoots out of the reach of grazing animals.

Apical dominance

In botany, apical dominance is the phenomenon whereby the main, central stem of the plant is dominant over other side stems; on a branch the main stem of the branch is further dominant over its own side twigs.

Meristem Type of plant tissue involved in cell proliferation

The meristem is a type of tissue found in plants. It consists of undifferentiated cells capable of cell division. Cells in the meristem can develop into all the other tissues and organs that occur in plants. These cells continue to divide until a time when they get differentiated and then lose the ability to divide.

Pruning Selective removal of parts of a plant

Pruning is a horticultural, arboricultural and silvicultural practice involving the selective removal of certain parts of a plant, such as branches, buds, or roots.

Auxin Plant hormone

Auxins are a class of plant hormones with some morphogen-like characteristics. Auxins play a cardinal role in coordination of many growth and behavioral processes in plant life cycles and are essential for plant body development. The Dutch biologist Frits Warmolt Went first described auxins and their role in plant growth in the 1920s. Kenneth V. Thimann became the first to isolate one of these phytohormones and to determine its chemical structure as indole-3-acetic acid (IAA). Went and Thimann co-authored a book on plant hormones, Phytohormones, in 1937.

Espalier Horticultural and agricultural practice of pruning and tying branches to a frame or flat structure

Espalier is the horticultural and ancient agricultural practice of controlling woody plant growth for the production of fruit, by pruning and tying branches to a frame. Plants are frequently shaped in formal patterns, flat against a structure such as a wall, fence, or trellis, and also plants which have been shaped in this way.

Sympodial branching

Sympodial growth is a bifurcating branching pattern where one branch develops more strongly than the other, resulting in the stronger branches forming the primary shoot and the weaker branches appearing laterally. A sympodium, also referred to as a sympode or pseudaxis, is the primary shoot, comprising the stronger branches, formed during sympodial growth. The pattern is similar to dichotomous branching; it is characterized by branching along a stem or hyphae.

Tamarillo Species of plant

The tamarillo is a small tree or shrub in the flowering plant family Solanaceae. It is best known as the species that bears the tamarillo, an egg-shaped edible fruit. It is also known as the tree tomato, tomate de árbol, tomate andino, tomate serrano, blood fruit, tomate de yuca, tomate de españa, sachatomate, berenjena, chilto and tamamoro in South America, and terong Belanda in Indonesia. It is popular globally, especially in Peru, Colombia, New Zealand, Ecuador, Rwanda, Australia, and the United States.

Plant senescence Process of aging in plants

Plant senescence is the process of aging in plants. Plants have both stress-induced and age-related developmental aging. Chlorophyll degradation during leaf senescence reveals the carotenoids, such as anthocyanin and xanthophylls, which are the cause of autumn leaf color in deciduous trees. Leaf senescence has the important function of recycling nutrients, mostly nitrogen, to growing and storage organs of the plant. Unlike animals, plants continually form new organs and older organs undergo a highly regulated senescence program to maximize nutrient export.

Babaco Hybrid species of tree

The babaco, is a hybrid cultivar in the genus Vasconcellea from Ecuador. It is a hybrid between Vasconcellea cundinamarcensis, and Vasconcellea stipulata.

Axillary bud Embryonic shoot located in the axil of a leaf or branch

The axillary bud is an embryonic or organogenic shoot located in the axil of a leaf. Each bud has the potential to form shoots, and may be specialized in producing either vegetative shoots or reproductive shoots (flowers). Once formed, a bud may remain dormant for some time, or it may form a shoot immediately.

Biennial bearing bearing is a term used in pomology to refer to trees that have an irregular crop load from year to year. In the "on" year too much fruit is set, leading to small fruit size. Excess weight in the main branches can be too much for their mechanical resistance, causing them to break. Another major consequence is that flower induction will be lower, and the subsequent year will be "off" year.

Leptosphaeria coniothyrium is a plant pathogen. It can be found around the world.

This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnifying lens. This page provides help in understanding the numerous other pages describing plants by their various taxa. The accompanying page—Plant morphology—provides an overview of the science of the external form of plants. There is also an alphabetical list: Glossary of botanical terms. In contrast, this page deals with botanical terms in a systematic manner, with some illustrations, and organized by plant anatomy and function in plant physiology.

Grafting Horticultural technique of joining plant tissues to grow together

Grafting or graftage is a horticultural technique whereby tissues of plants are joined so as to continue their growth together. The upper part of the combined plant is called the scion while the lower part is called the rootstock. The success of this joining requires that the vascular tissues grow together and such joining is called inosculation. The technique is most commonly used in asexual propagation of commercially grown plants for the horticultural and agricultural trades.

Important structures in plant development are buds, shoots, roots, leaves, and flowers; plants produce these tissues and structures throughout their life from meristems located at the tips of organs, or between mature tissues. Thus, a living plant always has embryonic tissues. By contrast, an animal embryo will very early produce all of the body parts that it will ever have in its life. When the animal is born, it has all its body parts and from that point will only grow larger and more mature. However, both plants and animals pass through a phylotypic stage that evolved independently and that causes a developmental constraint limiting morphological diversification.

This glossary of viticultural terms list some of terms and definitions involved in growing grapes for use in winemaking.

Vine training Horticultural technique

The use of vine training systems in viticulture is aimed primarily to assist in canopy management with finding the balance in enough foliage to facilitate photosynthesis without excessive shading that could impede grape ripening or promote grape diseases. Additional benefits of utilizing particular training systems could be to control potential yields and to facilitate mechanization of certain vineyard tasks such as pruning, irrigation, applying pesticide or fertilizing sprays as well as harvesting the grapes.

Topophysis occurs when scions, buddings, or root cuttings continue to grow in the same way after grafting as they had while growing on the ortet.

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