Top Working Orchard Trees
( Originally Published Early 1900's )
T. F. BAKER, GRAND HAVEN.
The top working of orchard trees is becoming more widely practiced by up-to-date scientific orchardists every year. Many orchards, especially those planted before the era of scientific horticulture in Michigan, are found unsuitable to the climate and other environmental conditions about them. To take out these old orchards and rejuvenate them with young suitable trees would require much patience and capital; to leave the trees unchanged means the continuance of an unproductive investment. Here the system of top working lends the orchardist a glad hand. By inserting buds or scions in the tops of his old trees, he can within a few years, completely change the fruit and character of his orchard. Again top working is practiced in trees of self sterile varieties to insure cross pollination. It is also used in reforming tops of trees like the peach, and is especially useful in testing out new varieties by bringing them into early bearing by working them into bearing trees. Furthermore, by selecting suitable stocks or scions, the danger from sun-scald may be lessened, vigor may be modified, fruit-fulness may be hastened, insect injuries decreased, and last, but not least, desirable characteristics may be perpetuated.
Scions inserted in old trees bear at an early age, but it is uncertain whether the fruiting of scions grafted on a young tree is accelerated.
Young trees top-worked with buds or scions from bearing trees will bear a year or two earlier than trees propagated with buds from nursery stock.
From this we. see that top-working is practical on both young and old trees. On young trees budding, whip and tongue, cleft and branch grafting are used. All the processes of grafting involve the insertion of a scion on the stock so that the growing parts of both are in contact. The operation is performed in the spring just before the foliage starts to push forth though it may be done a little earlier or later.
The process of budding consists in the insertion of a bud attached to a piece of bark into a slit or matrix in the stock. Shield budding is most commonly practiced, and is so named from the shape of the bud with its adherent back. The best time for budding is early September. The young tree may be either body or branch budded. In the latter case the buds are placed several inches from the stem so that in case the fall bud dies another may be set the following June or September. As soon as the bud commences growth in the spring, the branch is cut off at a distance of about 2 inches above the bud. This to prevent the new shoot from blowing out. After a few weeks the stub is cut off close to the shoot, so it may heal over during that sea-son. It is sometimes advisable to leave the water sprouts from a June budded tree or limb until the following spring as this checks the growth of the new shoot at the same time giving it a better chance to harden. On the other hand, fall budded branches demand the removal of water sprouts three or four times during the following season to prevent smothering.
In working new varieties on old trees the cleft graft is invariably used. The process consists in the splitting of the limb longitudinally and the insertion of 2 scions one on each end of the slit so that the growing portions of scion and stock are in contact with each other. This is done in early spring on limbs not exceeding 3 inches in diameter as those larger than this are not likely to heal over. Both the cleft in the stock and the tips of the cions are carefully waxed after the operation. Both scions are allowed to grow for several weeks during the following season, and then the weaker is selected and cut off, throwing the total vitality into the one shoot. It is best not to try to remove the entire top in a single year, as it is at least an exhaustive process, and should therefore be spread over a period of a few years. Water sprouts should be removed in June; it is also best to paint the larger wounds with thick lead, to prevent the entrance of water, spores of fungus diseases and bacteria.
A good, well known grafting wax is compounded as follows:
1 part tallow.
2 parts beeswax.
4 parts resin.
This is melted, poured into a pan of water and pulled like molasses candy until light colored. It may be kept indefinitely by wrapping in oiled paper and placing it in water.