Apple/Pear seeds collected from a particular variety will not produce true-to-type. To make an exact copy of any selected apple variety, it needs to be spring grafted or summer budded.
Grafting is the process by which a piece of one kind of plant is attached to a different kind of plant (such as a Fuji apple twig on a seedling apple rootstock).
To utilize the technique of dormant spring grafting which we will conduct in March ... A shoot or twig (known as a scion or scion wood) is collected in January through March and stored under refrigeration until grafting season. The process of grafting itself is quite simple. A selected piece of scion wood is inserted into the rootstock of a young apple/pear tree where, over time, it will heal and fuse together make a new tree.
The most important point in collecting scion wood is to be sure to collect new growth; that is, twigs or shoots that emerged the previous summer. New growth is identified by its smooth, reddish or greenish bark in contrast to older growth which will have rough, grayish-colored bark. New growth will have small, tight buds and rarely have side limbs, twigs or branches which are common on older growth. The two photographs below are examples of good and bad scion wood. Notice in Fig.1 the relatively smooth cuttings with small buds. This one-year-old wood is excellent grafting material.
Fig.2 shows two and three-year-old fruiting wood which is unsuitable for grafting. However, the cutting in the middle of Fig.2 shows a short length of wood at the top which is good viable scion wood. Frequently on older trees this is the best material that can be collected.
On older, unmanaged trees, new growth can be very difficult to find. Normally, this new growth can be found out on the tips of twigs high up on the sunny side of the tree. You can also find new growth on water sprouts which are vigorous, whip-like shoots ranging in size from a couple of inches to several feet in length and typically found growing vertically upwards from the trunk or larger limbs. Not all water sprouts are new growth, however. Be sure that any water sprout selected for scion wood has no side limbs or twigs on it.
Collect the proper scion wood cuttings in late January to mid March. The cuttings should ideally be eight to twelve inches in length and approximately the diameter of a pencil, although pieces of a smaller length and diameter can be successfully grafted. Bundle the scion wood together and label each variety separately. Wrap the bundles in a damp (not wet) newspaper and enclose tightly in Saran Wrap or a gallon zip lock plastic bag, and store in your refrigerator until the scion exchange.
Tips on Cutting & Storing Scions: (Hints for Everyone)
1. Look around your garden. What do you have (that is dormant) that could be pruned to yield scions for grafting, budding, or rooting? What could you bring to the Exchange as bareroot plants?
2. Cut scions and dig plants as close to the Exchange date as possible, while the donor plant is still dormant but BEFORE the buds begin to swell. (Some of your prunings may be too old and hard to be useful, while others may be too young and tender. A book like Sunset Pruning and Grafting can help you decide what to keep and what to discard for any given species. Or bring the prunings to the Exchange and ask for help.)
3. Carefully remove leaves and leaf litter from your plant materials. Light Brown Apple Moth (a new plant pest with many hosts) hides in both living and dead leaves. For evergreen scions (i.e., citrus), trim off the leaf blade but leave the petiole attached to the scion.
3. Cut each scion 4 to 8" long. Aim to have at least 4 buds on each piece. Cut the bottom of each piece square and the top end at a diagonal so others can tell which end is up.
4. Label your scions and store them in plastic bags to prevent drying. Or you can dip both ends of each piece in melted paraffin. Keep roots of bareroot plants in damp sawdust or damp, leaf-free, dirt.
5. Store scions in the refrigerator (NOT IN THE FREEZER), a COLD basement, or buried in the ground.
6. Before coming to the Exchange, place all the scions of one kind together in a plastic bag, preferably a 1-gal ZIPLOC bag to preclude the bother of twist-ties. Label each bag.
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