Apple Growing Part 3

FRUIT THINNING.--A matter which is quite nearly related to pruning is thinning the fruit, and may properly be treated here. That this is not as common a practice with most fruit-growers as it should be, the great lack of uniformity in our ordinary market apples is ample evidence. Many persons will at once raise the question as to whether or not it is practicable to thin the fruit on large apple trees. The answer is that many growers find it not only practicable, but most profitable to do so. Wherever fruit of a uniform size and color is desired, thinning is a practical necessity, especially when the crop of fruit is heavy.

The proper time to thin the fruit is just after what is commonly known as the "June drop," i.e., the falling off of those fruits not well enough pollinated or set to hold on to maturity. In thinning the fruit should be taken off until they are not closer than from four to six inches apart on the same branch, although the distance apart on any branch will depend somewhat on the amount of the crop on other parts of the tree. Never leave cl.u.s.ters of fruit on any branches, as some of them are sure to be small and out of shape. Furthermore two apples lying together afford a fine place for worms to get from one apple to another and they seldom fail to improve the opportunity. Step ladders and ordinary rung ladders are used to get at the fruit for thinning.

The cost of the operation is not nearly as large as might appear at first thought and in practically all cases is a paying investment.

CHAPTER V

CULTIVATION AND COVER CROPPING

In its broad sense cultivation is the treatment of the soil. Thus understood orchard cultivation includes the sod mulch system as well as the stirring of the soil with various implements. In its more common and restricted meaning, however, cultivation is the stirring of the soil about plants to encourage growth and productivity. To have the apple tree in sod was once the commonly accepted method of orchard treatment--a method of neglect and of "letting well enough alone."

With the advent of more scientific apple culture the stirring of the soil has come to be the more popular method. But within the last few years an improved modification of the old sod method, known as the sod "mulch" system, has attracted much attention because of the success with which a few men have practiced it. For a correct understanding of these practices and of the relative desirability of these systems we must again turn to underlying principles and purposes.

It may be said on first thought that tillage is a practice contrary to nature. But it accomplishes what nature does in another way. Tillage has been practiced on other crops than trees for so long that we think of it almost as a custom. There are, however, scientific and practical reasons for tillage.

THE EFFECTS OF TILLAGE on the soil are three fold, physical, chemical, and increasing of water holding capacity. Tillage affects the soil physically by fining and deepening it, thus increasing the feeding area of roots, and by bringing about the more free admission of air warms and dries the soil, thus reducing extremes of temperature and moisture. Chemical activities are augmented by tillage in setting free plant food, promoting nutrification, hastening the decomposition of organic matter, and the extending of these agencies to greater depth.

Tillage conserves moisture by increasing the water holding capacity of the soil and by checking evaporation.

Of all these things which tillage accomplishes in a soil, two should be especially emphasized for the apple orchard, namely, soil moisture and soil texture. That moisture is a very important consideration in the apple orchard the effects of our frequent droughts are ample evidence. The amount of rainfall in the Eastern States when it is properly distributed is fully sufficient for the needs of an apple tree. By enlarging the reservoir or water holding capacity of the soil and by preventing the loss of water by evaporation, an excess of rainfall in the spring may be held for later distribution and use.

As a rule, the improvement of a poor soil texture is as effective as the supplying of plant food and much cheaper. The latter is of no consequence unless the plant can use it. Scientists tell us that there is an abundance of plant food in most soils. The problem is to make it available. Plant food must be in solution and in the form of a film moisture surrounding the smallest soil particles in order to be available to the fine plant rootlets which seek it. Good tillage supplies these conditions. Can they be obtained equally well in another way?

It is claimed by the advocates of the sod mulch system of orchard culture that it also supplies these conditions. Humus or decayed vegetable matter holds moisture. Gra.s.s or other mulch decaying in the soil increases its humus content and hence its water holding capacity.

By forming a mulch over the soil evaporation may be checked to some extent, although probably not as effectively in a practical way, as by cultivation. If there is a good gra.s.s sod in the orchard, moisture and plant food made available by that moisture are utilized, and if the gra.s.s is allowed to go back into the soil it continues to furnish these elements to the tree. But there is a rapid evaporation of moisture from the surface of the leaves of gra.s.s. In fact, gra.s.s may well serve to remove an excess of moisture in wet seasons, or from wet lands.

Laying aside theoretical considerations, let us see what practical experience teaches on this subject. We have the accurate data on a large number of western New York orchards showing the results of cultivation and other methods of soil management. These data are overwhelmingly in the favor of cultivation. In Wayne County the average yield of orchards tilled for five years or more was 271 bushels per acre, as compared with 200 bushels per acre for those in sod five years or more but otherwise well cared for,--an increase of thirty-five per cent. in favor of good tillage. In Orleans County, under the same conditions, the increase in yield due to cultivation was forty-five per cent. and in Niagara County it was twenty-two per cent. Records were made on hundreds of orchards and the results should be given great weight in determining the system to be practiced, as intelligent consideration of trustworthy records is to be encouraged.

These results were obtained in one region under its conditions and it is quite possible, although not probable, that other conditions might give different results. There are, however, special conditions as will be pointed out later, under which the sod mulch method might be more advisable than tillage. It is cheaper, makes a cleaner cover for the drop fruit, avoids the damage from tillage implements to which tilled trees are liable, and can be practiced on lands too steep to till. It often happens, too, that it fits into the scheme of management on a general farm better than the more intensive and specialized system of cultivation. And it must be remembered that we are dealing with this question from the point of view of the home farm rather than of the commercial orchardist. So that where the sod mulch gives equally good results it would be preferred under these conditions.

LATE FALL AND EARLY SPRING PLOWING.--The common tillage practice in the sections where it is most followed is to plow either in late fall or as early as possible in the spring. Whether fall or spring plowing is best depends on two things: the character of the soil and convenience. On heavy clay soils where drainage is poor it is not advisable to plow in the fall as the soil is apt to puddle and then to bake when it dries, making it hard to handle. On gravel loams, medium loams, and all well drained soils which are fairly open in texture either fall or spring plowing is practiced depending on which period affords the most time.

On the general farm where there are several crops for which the land must be prepared in spring, it would seem best to get as much of the plowing as possible done in the fall. But a large crop of apples or a large and late corn husking or potato digging may interfere with this on some farms and make spring plowing more desirable. Always plan this work in connection with the other farm work so as to give the best distribution of labor.

After fall plowing either the spring-tooth harrow or the disk harrow is best to use to work up the soil and no time should be lost in getting at this as soon as the land is dry enough in the spring.

Sometimes the disk harrow can be used to work up the soil in the orchard in the spring without any plowing at all, especially on loose loams where there are few stones. But on newly plowed land a disk cuts too deep and there is too great danger of injuring the roots. On spring plowed land the spring-tooth harrow usually gives the best results. After the soil is thoroughly fined and worked into a mellow bed and as soon as the period of excessive moisture in spring is pa.s.sed, a lighter implement like the smoothing harrow or a light shallow digging cultivator should be used to stir the surface of the soil only.

The growing period for an apple tree begins as early as growth starts in the spring and continues up to about midsummer. If cultivation is to stimulate growth as much as possible, it should be done during this period. The first object of cultivation in the early spring is to loosen up, aerate, and dry out the soil, which is usually too wet at that time. As cultivation is continued the soil will become fined and firmed again by the time drier weather comes on. A fairly deep digging and lump crushing tool is the best implement to use up to this time, and a disk or spring-tooth harrow meets these requirements.

After this period is pa.s.sed and during drier weather, cultivation is carried on for a different purpose, namely, to conserve moisture by making a thin dust mulch of soil over the surface. This is best accomplished by shallow-going implements of which the spike-tooth harrow, the acme harrow, or a light wheel cultivator are best. As the season and the amount of rainfall vary, so must tillage operations be varied. In an early dry season begin with the lighter implements earlier. In a late wet season keep the digging tools at work later. As soon as the soil is in good physical condition the princ.i.p.al object of tillage is to modify moisture conditions.

As a matter of practice three to four harrowings at intervals of a week to ten days are necessary. Sometimes more, sometimes less are required, according to the character and condition of the soil and the season. The later moisture-conserving tillage should also be carried on every week or ten days, according to weather conditions. It is good practice to stir the soil after every heavy or moderately heavy rain.

Use the smoothing tools after light to medium rains and the heavier tools after packing or beating rains. In practice from five to eight or ten of these cultivations are necessary. The drier the season the more necessary does frequent cultivation become.

A COVER CROP is so closely a.s.sociated with tillage that it is usually considered a part of the system. It should be sown in midsummer as soon as tillage ceases. This time will vary from July first to August fifteenth, depending on the locality, the rainfall, the crop of fruit on the trees, and on how favorable the conditions for securing a good stand of the cover crop are. The farther south the locality, or the earlier the fruit, the sooner the crop should be sown. Absence of sufficient rainfall necessitates a continuation of the cultivation, both because it is necessary to conserve all the moisture possible and because it is difficult to get a good stand of a cover crop--especially of one having small seeds--at a dry time in midsummer.

In a year when there is a full crop of fruit on the trees cultivation should be continued as late as possible as all the stimulus that can thus be secured will be necessary to help the fruit attain good size and maturity, and at the same time enable the tree properly to mature its fruit and leaf buds for the following year. On the other hand, in a year when there is not a full crop of fruit cultivation should be stopped early so as to avoid forcing a too rank growth of wood and foliage and continuing the growth of the next season's buds so late that they may not mature and therefore may be in danger of winter killing.

The different kinds of cover crops which may be used in the apple orchard will be considered in the next chapter as they are so closely a.s.sociated with fertilization. Strictly speaking, however, a cover crop is used princ.i.p.ally to secure its mulching and physical effects on the soil in the intervals between the seasons of tillage. In addition to its physical and feeding effects the cover crop serves to check the growth of trees in the latter part of the season by taking up the nitrates and a part of the moisture, thus helping to ripen the wood.

SOD MULCH.--The ordinary sod culture which is practiced in so many orchards should not be confused with the sod mulch system. The one is a system of neglect, the other of intention. In the sod mulch system the gra.s.s sod is stimulated and encouraged and when the gra.s.s dies or is cut, it is left on the ground to decay, forming a soil mulch meanwhile. The removal of gra.s.s from the orchard as hay is poor practice and should be discouraged. The gra.s.s mulch may well be supplemented by the addition of other gra.s.s, straw, leaves, coa.r.s.e manure, or other similar materials. Sometimes this mulch is put on to the depth of six inches or even a foot around the tree. Thus practiced it is very effective in conserving moisture and in adding the humus which is so necessary to the soil.

Sod and tillage have somewhat different effects on the tree and on the fruit. Let us see what these effects are. It is common knowledge that fruit is more highly colored when grown in sod than when grown under a tillage system. This is probably largely due to the fact that tillage keeps the fruit growing so late that it does not mature so well or so early. Fruit is usually two or three weeks later in tilled than in sod orchards. It has been shown that fruit grown under tillage keeps from two to four weeks longer than that grown in sod. It is claimed also--but this is a disputed point--that tilled fruit has a better quality and flavor. Certain it is that fruit grown in sod is drier and less crisp and juicy.

The effect of tillage on the trees is more marked and better known.

Tilled trees have a darker, richer green foliage, indicating a better and more vigorous health. The leaves are also larger and more numerous. They come out three or four days earlier in the spring and stay on the trees two weeks later in the fall than the leaves on trees kept in sod. Tilled trees make nearly twice the growth in a season that those in sod do, in fact there is danger of their making wood growth at the expense of fruit buds. Tillage also gives a deeper, better distributed root system.

Despite the advantages and the disadvantages of each system, there are times, places, and circ.u.mstances under which one is more advisable than the other. On lands rich in humus and in plant food and level so as to be easily tillable, cultivation is without doubt the best system. But it should be practiced in connection with cover crops, and the orchard should be given occasional periods of rest in sod--say one year in from three to five.

The sod mulch system of orchard culture is probably better adapted to rather wet good gra.s.s land and where mulching material is cheap and readily available. It is undoubtedly at its best on lands too steep or rough to till, or otherwise unsuitable to cultivation. Tillage is the more intensive method and where labor is scarce and high sod culture might be more advisable for this reason, other conditions being not too unfavorable.

In order to ill.u.s.trate a method of management under the tillage system we may suggest the following as a good one for level to gently rolling land:

1912. Early plowing in spring, cultivation to July first to fifteenth. Then sow red clover as a cover crop.

1913. Repeat previous year's treatment, varying the time of sowing cover crop according to conditions.

1914. Let the clover grow, mowing and leaving on the ground as a mulch, June fifteenth to twentieth, and again in August.

1915. Plow early in spring, cultivate to midsummer, and then sow rye or buckwheat as a cover crop July fifteenth to August fifteenth.

1916. Repeat 1915 treatment and if trees are not growing too fast, sow clover or hairy vetch as a cover crop.

1917. Same as 1912, etc.

PASTURING THE ORCHARD.--The sod mulch system explains itself and does not need ill.u.s.tration. Sod orchards are often managed as pasture for animals, however, and this practice should be discussed. An orchard is considered as pastured when a considerable number of animals are turned into it for a greater or less portion of the year. Results in orchards where pasturage has been thoroughly tried out show that it is never advisable to pasture an orchard with horses or cattle, but that fairly good results may be expected where sheep or hogs are used.

The evidence of yield of fruit and appearance of trees both indicate, that pasturing an orchard with horses or cattle is about the worst possible practice. These animals rub against the trees, break the branches, browse the limbs and leaves, and destroy the fruit as high as they can reach. All experience is against this practice which cannot be too strongly deprecated.

Pasturing an orchard with sheep, although a somewhat doubtful practice, often gives good results. Sheep crop the gra.s.s close to the ground and to some extent prevent the extensive evaporation which usually takes place from the leaves of gra.s.s. Their well distributed manure is worth considerable. They also browse the branches to some extent and should not be allowed to run in the orchard late in the season as they will destroy considerable fruit.

Pasturing an orchard with swine gives better results than any other pasture treatment of the orchard. Hogs do considerable rooting which prevents the formation of a stiff sod and itself may often amount almost to cultivation in well stocked orchards. A good deal of manure is added to the soil, especially when the hogs are fed outside the orchard. Hogs also destroy many insects by eating the wormy fruit.

Pasturage of orchards has its advantages. It gives a double utilization of the land. It is a cheap method of management. When the animals are fed outside the orchard, as should always be the case, it adds considerable plant food to the soil. When plenty of outside food can be given and when the orchard is not overstocked--the animals should never be hungry--hogs and sheep may be used to advantage in pasturing orchards. In very rough fields incapable of tillage, this is undoubtedly the very best system of orchard management.

Pasturage has the disadvantage of exposing young trees to injury from the animals, but this may be at least partly avoided by protecting them with stakes or a heavy wire meshed screen. Hogs especially soil the fruit and make the land rough and difficult to drive over. Under the proper conditions pasturage may be practiced to advantage, especially on small areas and on the general farm where it is more advantageous than it would be commercially.

CHAPTER VI

MANURING AND FERTILIZING

Cover crops may be said to be supplementary to tillage. In the previous chapter this function has been discussed. It now remains to point out another important function--that of a green manure crop adding humus and plant food to the soil. Not only do some cover crops add plant food and all humus to the soil, but they tend to conserve these by preventing leaching, especially of nitrates, and they help to render plant food more available by reworking it and leaving it in a form more available for the tree. They sometimes act as a protection against winter injury by holding snow and by their own bulk. They also help to dry out the soil in spring, thus making the land tillable earlier.