WW-00532 Reviewed 2009
Young, vigorous fruit trees up to 5 years old are best for topworking. Older apple and pear trees of almost any age can be topworked but the operation is more severe and those over 10 years old must be worked at a higher point. Hibernal, Columbia, or Virginia crab, because of their 3 vigor and their strong, well-placed branches, are very good understocks.
Young trees should have 1 to 2 feet of branch between the trunk and the graft. Otherwise the good crotch formation of the understock will be lost by the trunk expanding past the union.
Trees up to 5 years old can be grafted at one time. On older trees about halfthe upper and center part onlyshould be worked at one time. The remainder should be worked a year later.
Scions are selected from the previous season's growth, while they are dormant, but before growth begins in the spring. If the scions are left on the tree until spring, however, there is some danger that the buds will start to grow or be injured during winter. Scions cut in November grow best in Minnesota.
The scions should be tied securely, carefully labeled and placed in moist (not wet) sawdust or moss or wrapped in plastic material. They should be kept in a cool, moist place where they will remain fresh and dormant until spring.
It is best to graft in the spring, from the time the buds of understock trees are beginning to open, until blossom time. The usual time is April or early May.
- Budding knife
- Grafting knife
- A fine-tooth saw for cleft grafting
- Pruning shears
- Dormant scions (cultivar labeled)
- Tying material such as grafting tape, adhesive tape, electrician's ber tape or rubber strips
- Asphalt water emulsion compound for covering grafts
- A light hammer for bridge grafting
- A cleft-grafting chisel and mallet, or a heavy knife or hatchet can be used for a small job
All grafts should be covered with a protective coating immediately after completing the graft.
Electrician's tape is an excellent material that will bind and protect graft unions. Choose a brand that is elastic and amply adhesive. A good tape for the purpose will stick well to itself. Do not stretch this tape too tightly or it may crack or weather. Better brands will last throughout the first summer, after which the tape is no longer needed.
Asphalt water emulsion is now widely used as a protective coating on graft unions. It is of pasty consistency and can be applied with a brush. It is preferable, however, to smear it on thicker with a small paddle.
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