The day has gone, probably forever, when setting out fruit trees and giving them occasional cultivation, "plowing up the orchard" once in several years, would produce fruit. Apples and pears and peaches have occupied no preferred position against the general invasion of the realm of horticulture by insect and fungous enemies. The fruits have, indeed, suffered more than most plants.
Nevertheless there is this encouraging fact: that, though the fruits may
have been severely attacked, the means we now have of fighting fruit-tree enemies, if thoroughly used, as a rule are more certain of accomplishing their purpose, and keeping the enemies completely at bay, than are similar weapons in any other line of horticultural work.
With fruit trees, as with vegetables and flowers, the most important precaution to be taken against insects and disease is to have them in a healthy, thriving, growing condition. It is a part of Nature's law of the survival of the fittest that any backward or weakling plant or tree seems to fall first prey to the ravages of destructive forces.
For these reasons the double necessity of maintaining at all times good fertilization and thorough cultivation will be seen. In addition to these two factors, careful attention in the matter of pruning is essential in keeping the trees in a healthy, robust condition. As explained in a previous chapter, the trees should be started right by pruning the first season to the open-head or vase shape, which furnishes the maximum of light and air to all parts of the tree. Three or four main branches should form the basis of the head, care being taken not to have them start from directly opposite points on the trunk, thus forming a crotch and leaving the tree liable to splitting from winds or excessive crops. If the tree is once started right, further pruning will give little trouble. Cut out limbs which cross, or are likely to rub against each other, or that are too close together; and also any that are broken, decayed, or injured in any way. For trees thus given proper attention from the start, a short jackknife will be the only pruning instrument required.
The case of the old orchard is more difficult. Cutting out too many of
the old, large limbs at one time is sure to give a severe shock to the vitality of the tree. A better plan is, first, to cut off close all suckers and all small new-growth limbs, except a few of the most promising, which may be left to be developed into large limbs; and then as these new limbs grow on, gradually to cut out, using a fine-tooth saw and painting the exposed surfaces, the surplus old wood. Apples will need more pruning than the other fruits. Pears and cherries need the least; cutting back the ends of limbs enough to keep the trees in good form, with the removal of an occasional branch for the purpose of letting in light and air, is all the pruning they will require. Of course trees growing on rich ground, and well cultivated, will require more cutting back than those growing under poorer conditions. A further purpose of pruning is to effect indirectly a thinning of the fruit, so that what is grown will be larger and more valuable, and also that the trees may not become exhausted by a few exceptionally heavy crops. On trees that have been neglected and growing slowly the bark sometimes becomes hard and set. In such cases it will prove beneficial to scrape the bark and give a wash applied with an old broom. Whitewash is good for this purpose.
Where extra fine specimens of fruit are desired, thinning is practiced. It helps also to prevent the tree from being overtaxed by excessive crops. But where pruning is thoroughly done this trouble is usually avoided. Peaches and Japan plums are especially benefited by thinning, as they have a great tendency to overbear. The spread of fruit diseases, especially rot in the fruit itself, is also to some extent checked.
Of fruit-tree enemies there are some large sorts which may do great damage in short order--rabbits and field mice. They may be kept away by mechanical protection, such as wire, or by heaping the earth up to a height of twelve inches about the tree trunk.
Insects and scale diseases are not so easily managed; and that brings us to the question of spraying and of sprays.
For large orchards the spray must, of course, be applied with powerful and expensive machinery. For the small fruit garden a much simpler and very moderate priced apparatus may be acquired. The most practical of these is the brass-tank compressed-air sprayer, with extension rod and mist-spray nozzle. Either of these will be of great assistance not only with the fruit trees, but everywhere in the garden. With care they will last a good many years. Whatever type you get, be sure to get a brass machine; as cheaper ones, made of other metal or plastic , quickly corrode from contact with the strong chemicals used.
For help in determining the type of infestation contact your County Cooperative Extension Service office. County Cooperative Extension Service offices are usually listed in the telephone directory under county or state government; these offices often have a range of resources on garden care and maintenance, including plant selection, pest control, and soil testing.
The insects most commonly attacking the apple are the codlin-moth, tent-caterpillar, canker-worm and borer. The codlin-moth lays its eggs on the fruit about the time of the falling of the blossoms, and the larvae when hatched eat into the young fruit and cause the ordinary wormy apples and pears. Owing to these facts, it is too late to reach the trouble by spraying after the calyx closes on the growing fruit. Keep close watch and spray immediately upon the fall of the blossoms, and repeat the spraying a week or so (not more than two) later. During July, tie strips of burlap or old bags around the trunks, and every week or so destroy all caterpillars caught in these traps. The tent-caterpillar may be destroyed while in the egg state, as these are plainly visible around the smaller twigs in circular, brownish masses.
The railroad-worm, a small white maggot which eats a small path in all directions through the ripening fruit, cannot be reached by spraying, as he starts life inside the fruit; but where good clean tillage is practiced and no fallen fruit is left to lie and decay under the trees, he is not apt to give much trouble.
The borer's presence is indicated by the dead, withered appearance of the bark, beneath which he is at work, and also by small amounts of sawdust where he entered. Dig him out with a sharp pocket-knife, or kill him inside with a piece of wire.
The most troublesome disease of the apple, especially in wet seasons, is the apple-scab, which disfigures the fruit, both in size and in appearance, as it causes blotches and distortions.
The San Jose scale is of course really an insect, though in appearance it seems a disease. It is much more injurious than the untrained fruit grower would suppose, because indirectly so. It is very tiny, being round in outline, with a raised center, and only the size of a small pinhead. Where it has once obtained a good hold it multiplies very rapidly, makes a scaly formation or crust on the branches, and causes small red-edged spots on the fruit . For trees once infested, spray thoroughly both in fall, after the leaves drop, and again in spring, before growth begins.
CHERRY ENEMIES Sour cherries are more easily grown than the sweet varieties, and are less subject to the attacks of fruit enemies. Sweet cherries are troubled by the curculio, or fruit-worm, which attacks also peaches and plums. Cherries and plums may be sprayed, when most of the blossoms are off.
Do not spray peaches. For the curculio, within a few days after the flowers are off, take a large sheet of some cheap material to use as a catcher. For large orchards there is a contrivance of this sort, mounted on a wheelbarrow frame, but for the home orchard a couple of sheets laid upon the ground, or one with a slit from one side to the center, will suffice. If four short, sharp-pointed stakes are fastened to the corners, and three or four stout hooks and eyes are placed to reunite the slit after the sheet is placed about the tree, the work can be more thoroughly done, especially on uneven ground. After the sheet is placed, with a stout club or mallet, padded with a heavy sack or something similar to prevent injury to the bark, give a few sharp blows, well up from the ground. This work should be done on a cloudy day, or early in the morning--the colder the better--as the beetles are then inactive. If a considerable number of beetles are caught the operation should be repeated every two or three days. Continue until the beetles disappear.
Peaches are troubled also by borers, in this case indicated by masses of gum, usually about the crown. Dig out or kill with a wire, as in the case of the apple-borer. Look over the trees for borers every spring, or better, every spring and fall.
Another peach enemy is the "yellows," indicated by premature ripening of the fruit and the formation of stunted leaf tufts, of a light yellow color. This disease is contagious and has frequently worked havoc in whole sections. Owing to the work of the Agricultural Department and the various State organizations it is now held in check. The only remedy is to cut and dispose of the trees and replant, in the same places if desired, as, the disease does not seem to be carried by the soil.
Pears are sometimes affected with a scab similar to the apple-scab, and this is combated by the same treatment of spraying
A blight which causes the leaves suddenly to turn black and die and also kills some small branches and produces sores or wounds on large branches and trunk, offers another difficulty. Cut out and dispose of all affected branches and scrape out all sores.
Plums have many enemies but fortunately they can all be effectively checked. First is the curculio, to be treated as described above.
For leaf-blight--spotting and dropping off of the leaves about midsummer- thin out the fruit so that it does not hang thickly enough for the plums to come in contact with each other.
In a well kept and well sprayed orchard black-knot is not at all likely to appear. It is very manifest wherever it starts, causing ugly, black, distorted knarls, at first on the smaller limbs. Remove and dispose of immediately, and keep a sharp watch for more. As this disease is supposed to be carried by the wind, see to it that no careless neighbor is supplying you with the germs.
The quality of fruit will depend very largely upon the care exercised in picking and storing. Picking, carelessly done, while it may not at the time show any visible bad results, will result in poor keeping and rot. If the tissue cells are broken, as many will be by rough handling, they will be ready to cause rotten spots under the first favorable conditions, and then the rot will spread. Most of the fruits of the home garden, which do not have to undergo shipping, will be of better quality where they ripen fully on the tree. Pears, however, are often ripened in the dark and after picking, especially the winter sorts. Apples and pears for winter use should be kept, if possible, in a cold, dark place, where there is no artificial heat, and where the air will be moist, but never wet, and where the thermometer will not fall below thirty-two degrees. Upon exceptionally cold nights the temperature may be kept up by using an oil stove or letting in heat from the furnace basement, if that is adjacent. In such a place, store the fruit loosely, on ventilated shelves, not more than six or eight inches deep. If they must be kept in a heated place, pack in tight boxes or barrels, being careful to put away only perfect fruit, or pack in sand or leaves. Otherwise they will lose much in quality by shriveling, due to lack of moisture in the atmosphere. With care they may be had in prime quality until late in the following spring.
Do not let yourself be discouraged from growing your own fruit by the necessity for taking good care of your trees. After all, you do not have to plant them every year, as you do vegetables, and they yield a splendid return on the small investment required. Do not fail to set out at least a few this year with the full assurance that your satisfaction is guaranteed by the facts in the case.