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SCH
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[[Image:Zweijährige-Geißfußveredelu.jpg|thumb|250px|right|Grafted apple tree ''Malus'' sp., consolidated 'V' graft]]
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[[Image:Upload.png|thumb|[[Special:Upload|Upload image!]]]]
[[Image:Newly_Grafted_Cherry_Tree.JPG|thumb|250px|right|''Newly grafted cherry tree'', tape has been used to bind the rootstock and scion at the graft and tar paint to protect the cut end of the scion from desiccation.  The buds will burst within the next few weeks to produce leaves and shoots]]
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The process of inserting a [[cion]] in a plant with the intention that it shall grow there. See ''[[Budding]]''.{{SCH}}
[[Image:Grafted blossoming tree unidentified white pink.JPG|thumb|250px|right|A grafted tree showing two different color blossoms]]
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'''Grafting''' is a technique used to join parts of 2 or more plants and cause them to grow together as one plant.  It is used quite commonly, and most fruit trees sold in nurseries tend to be grafts.  The most common reason for grafting is as a method of asexual [[plant propagation]]. It is most commonly used for the propagation of [[tree]]s and [[shrub]]s grown commercially.
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Usually, one plant is chosen for its roots, and is called the '''stock''' or [[rootstock]]. The other plant is chosen for its [[Plant stem|stems]], leaves, [[flower]]s, or [[fruit]]s and is called the '''scion'''.  The scion contains the desired genes to be duplicated on top of the stock plant.
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{{glossary}}
 
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In stem grafting, a common grafting method, a [[shoot]] of a selected, desired plant cultivar is grafted onto the stock of another type. In another common form called [[budding]], a dormant side bud is grafted on the stem of another stock plant, and when it has fused successfully, it is encouraged to grow by cutting out the stem above the new bud.
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For successful grafting to take place, the [[vascular cambium]] tissues of the stock and scion plants must be placed in contact with each other. Both tissues must be kept alive until the graft has taken, usually a period of a few [[week]]s. Successful grafting only requires that a vascular connection takes place between the two tissues. A physical weak point often still occurs at the graft, because the structural tissue of the two distinct plants, such as [[wood]] may not fuse.
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==Reasons for grafting==
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*'''Dwarfing''': To induce dwarfing or cold tolerance or other characteristics to the scion. Most [[apple]] trees in modern [[orchard]]s are grafted dwarf or semi-dwarf trees planted at high density. They provide more fruit per unit of land, higher quality [[fruit]], and reduce the danger of accidents by harvest crews working on ladders.
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*'''Ease of propagation''': Because the scion is difficult to propagate vegetatively by other means, such as by [[Cutting (plant)|cuttings]]. In this case, cuttings of an easily rooted plant are used to provide a rootstock. In some cases, the scion may be easily propagated, but grafting may still be used because it is commercially the most cost-effective way of raising a particular type of plant.
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*'''Hybrid breeding''': To speed maturity of hybrids in fruit tree breeding programs. Hybrid seedlings may take ten or more years to flower and fruit on their own roots. Grafting can reduce the time to flowering and shorten the breeding program.
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*'''Hardiness''': Because the scion has weak roots or the roots of the stock plants have roots tolerant of difficult conditions. e.g. many showy [[Western Australia]]n plants are sensitive to [[Phytophthora cinnamomi|dieback]] on heavy soils, common in urban gardens, and are grafted onto hardier [[eastern Australia]]n relatives. [[Grevillea]]s and [[Eucalyptus|eucalypts]] are examples. 
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*'''Sturdiness''' In order to provide a strong, tall [[trunk]] for certain ornamental shrubs and trees. In these cases, a graft is made at a desired height on a stock plant with a strong stem. This is used to raise 'standard' [[rose]]s, which are rose bushes on a high stem, and it is also used for some ornamental trees, such as certain weeping cherries.
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*'''Pollen source''': To provide [[pollenizer]]s. For example, in tightly planted or badly planned apple [[orchard]]s of a single variety, limbs of [[crab apple]] may be grafted at regularly spaced intervals onto trees down rows, say every fourth tree. This takes care of [[pollen]] needs at blossom time, yet does not confuse pickers who might otherwise mix varieties while harvesting, as the mature [[crab apple]]s are so distinct from other apple varieties.
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*'''Repair''': To repair damage to the trunk of a tree which would prohibit nutrient flow, such as the stripping of the bark by [[rodent]]s which completely girdles the trunk. In this case a [[bridge graft]] may be used to connect the tissues receiving flow from the roots to the tissues above the damage which have been severed from the flow. Where a [[watersprout]], sucker or sapling of the same species is growing nearby, any of these can be grafted to the area above the damage by a method called inarch grafting. These alternatives to scions must be of the correct length to span the gap of the wound.
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*'''Changing cultivars''': To change the cultivar in a fruit orchard to a more profitable cultivar, called ''topworking''. It may be faster to graft a new cultivar onto existing limbs of established trees than to replant an entire orchard.
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*'''Maintain Consistency''':  Apples are notorious for their genetic variability, even differing in multiple characteristics, such as, size, color, and flavor, of fruits located on the same tree.  In the commercial farming industry, consistency is maintained by grafting a scion with desired fruit traits onto a hardy stock.
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[[Image:Neadle.jpg|thumb|250px|right|An example world-famous Circus Trees created by Axel Erlandson.[1]]]
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*'''Curiosities'''
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**A practice sometimes carried out by [[gardener]]s is to graft related [[potato]]es and [[tomato]]es so that both are produced on the same plant, one above ground and one underground.
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**[[Cacti]] of widely different forms are sometimes grafted on to each other.
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**Multiple [[cultivar]]s of fruits such as apples are sometimes grafted on a single tree. This so-called "[[Fruit Salad Tree|family tree]]" provides more fruit variety for small spaces such as a suburban backyard, and also takes care of the need for pollenizers. The drawback is that the gardener must be sufficiently trained to [[pruning|prune]] them correctly, or one strong variety will usually "take over". Occasionally, a so-called "[[Graft-chimaera|graft hybrid]]" or "chimaera" can occur where the tissues of the stock continue to grow within the scion. Such a plant can produce flowers and [[foliage]] typical of both plants as well as shoots intermediate between the two. The best-known example is probably [[+Laburnocytisus 'Adamii'|+''Laburnocytisus'' 'Adamii']], a graft hybrid between [[laburnum]] and [[broom (shrub)|broom]], which originated in a [[nursery (horticulture)|nursery]] near [[Paris|Paris, France]] in [[1825]]. This small tree bears yellow flowers typical of ''Laburnum anagyroides'', purple flowers typical of ''Chamaecytisus purpureus'' and curious coppery-pink flowers which show characteristics of both "parents".
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**Ornamental and functional, [[arborsculpture]] uses grafting techniques to join separate trees or parts of the same tree to itself. [[Furniture]], hearts, entry archways are examples. [[Axel Erlandson]] was a prolific arborsculptor growing over 75 mature shaped and grafted trees.
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== Methods ==
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=== Cleft ===
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The easiest and most common form of grafting is cleft grafting. The stock is simply split and  the scion is inserted. It is best if the stock is 2-7 cm in diameter and has 3-5 buds, and the cleft is around 7cm deep. The scion is cut in a [[wedge (geometry)|wedge]] shape and inserted into the tree with the cambium.  The bare stock is covered with grafting compound, otherwise the cambium layer quickly dries and the graft fails.
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=== Stub ===
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Stub grafting is a technique that requires less stock than cleft grafting, and retains the shape of a tree. Also scions are generally of 6-8 buds in this process.
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An incision is made into the branch one centimetere long, then the scion is wedged and forced into the branch.  The scion should be at an angle of at most 35° to the parent tree so that the crotch remains strong.  The graft is covered with grafting compound.
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=== Awl ===
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Awl grafting takes the least resources and the least time must is best done by an experienced grafter for fear that the grafter would accidentally drive his tool too far into the stock and then the scion would have a reduced chance of survival. Awl grafting can be done by using a screwdriver to make a slit in the bark but just so far as the cambium layer. Then inset the wedged scion into the incision.
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=== Veneer ===
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Veneer grafting, or inlay grafting, is a method used for stocks larger than three centimeters in diameter. The scion is recommended to be about as thick as a pencil.  Clefts are made of the same size as the scion on the side of the branch, not on top.  The scion end is shaped as a wedge, inserted, and wrapped with tape to the scaffolding branches to give it more strength.
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=== Renewing fusion ===
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"Renewing fusion" is a grafting method in which a small branch (at least a centimeter wide) from one plant to a main branch of another, by carefully shaving a proper amount of bark from the large branch and inserting the scion into a cut hole.  The graft is taped with a thin strip of duct tape in diagonal lashings, to hold it up and to prevent insects from entering the hole.
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<!--The original section is below.  It would be nice if someone could correct it to make sense as it would still be useful info
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... find one the main branches on that tree, measure to make sure it is at least 3 inches long and 2 and a half inches long and divide by how long the branch is. Shave that many centimeters of the bark. Place the branch you would like to graft on the center of the shaved area then drill in the circle to the core of the branch then insert the twig.
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The origin of grafting is uncertain. the peoples of ancient civilizations who grew fruit trees may have observed natural unions made by twigs and branches of compatible trees growing next to one another.
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==Natural grafting==
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Tree roots of the same species will sometimes naturally graft where they make physical contact with each other. A group of trees can share water and mineral nutrients via root grafts, which may be advantageous to weaker trees, and may also form a larger rootmass as an adaptation to promote fire resistence and regeneration as exemplified by the [[California Black Oak]].<ref>C.Michael Hogan (2008) ''Quercus kelloggii'', Globaltwitcher, ed. nicklas Stromberg [http://www.globaltwitcher.com/artspec_info.asp?thingid=82385]</ref>
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A problem with root grafts is that they allow transmission of certain [[pathogen]]s, such as [[Dutch elm disease]]. Natural grafting also sometimes occurs where two stems on the same tree, shrub or vine make contact with each other. This is common in plants such as strawberries and potatoes.
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== Herbaceous grafting ==
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Grafting is often done for non-woody plants such as a [[tomato]], [[cucumber]], [[eggplant]] and [[watermelon]].<ref>{{cite web | last = Core | first =  J. | date =  2005 | title =  Grafting watermelon onto squash or gourd rootstock makes firmer, healthier fruit. | publisher = Agricultural Research | page =  53 | url = http://www.ars.usda.gov/is/AR/archive/jul05/fruit0705.htm }}</ref> The main advantage of grafting is for disease-resistant rootstocks. In [[Japan]] there is an automated process using grafting [[robot]]s.
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== References ==
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{{reflist}}
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==External links==
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* [http://www.omafra.gov.on.ca/english/crops/facts/98-003.htm#BRIDGE%20GRAFT Steps to inarching technique]
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* [http://cals.arizona.edu/pubs/garden/mg/propagation/grafting.html Asexual Propagation (with diagrams)]
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* [http://www.omafra.gov.on.ca/english/crops/facts/98-005.htm grafting methods (with diagrams)]
 

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