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What Treatment is Needed.
Summary statement.-The fruit- -grower will no doubt desire to ask how he is to tell just what kind and what quantity of fertilizers to apply to his land. This is one of those questions which no person can answer for him. Having studied the matter carefully, and having observed his plantation from day to day and year to year, he should be able to discover about the treatment which it needs. As a general statement, it may be said that, the fruit plantation which is giving satisfactory results is receiving the very treatment which it needs; but when it is giving unsatisfactory yields, some change in the management should be made. An orchard which is in sod and not doing well should certainly be plowed and tilled. One which is tilled and is not doing well may be benefited by seeding down, or it may not. If the growth is strong and rapid, and the trees or vines seem to be going to wood at the expense of fruit, then some check may be necessary. This check may be given by seeding down for a time, by giving somewhat less thorough or prolonged cultivation, or by the use of rather more mineral fertilizers and less nitrogenous ones. In all cases in which the growth is not sufficient and the leaves are yellow and drop early, it is probable that either more nitrogen or more moisture, or both, is needed. As a general principle, it may be said that nitrogen can be had in sufficient amount by thorough and judicious tillage, by the use of leguminous cover crops, and by stable manure. In some cases, however, quicker and cheaper results may be had by
the direct addition of nitrogenous materials, like nitrate of soda, sulfate of ammonia, or some of the animal compounds.
The grower should also remember that the plants need all the elements of plant growth, and not one of them alone. For example, a heavy application of nitrogen upon soil which is deficient in potash and phosphoric acid cannot be expected to give useful results. In the same way, the application of potash to soil which is very poor in nitrogen or phosphoric acid would be comparatively useless. The heavy loamy or clay lands nearly always contain an abundance of potash and phosphoric acid in a more or less unavailable condition, and much of these materials can be liberated to the plant by careful tillage and the incorporation of humus. However, it is nearly always advisable, in orchards which are bearing, to add these materials in the shape of manures or concentrated fertilizers. The quickest results following the use of fertilizers will be seen upon the sandier lands. Two or three years often elapse after the application of chemical fertilizers to heavy lands before any decided results are observed. In other words, clay lands ordinarily show quicker results from tillage than they do from the application of fertilizers. The farmer should bear in mind that he should never rely exclusively upon chemical plant-foods, because they contain no humus, and the soil is apt to become hard and lifeless. They should be used in judicious rotation, or in connection with cover crops, or stable manures,
Humus Improves the Land.
221 or applications of muck or some other organic dressings. It is not necessary that the chemical fertilizers should be mixed before application; in fact, upon lands of varying soil and conformation, it is ordinarily better to apply the different ingredients separately, because different parts of the plantation may need different amounts of the various materials. The low lands will ordinarily need less of the nitrogen and perhaps more of the potash and phosphoric acid. In general, it is advisable to buy the plantfoods separately, as advised in the preceding pages.
Farmers do not appreciate the importance of humus as an ameliorator of land. In farm lands, it is usually supplied in form of green crops, stubble or sward, and barn manures. When humus is absent, sandy soils become too loose and leachy and hot, and clay soils bake and become lumpy. The different physical characteristics of clay lumps and mellow soils are largely due to the greater amount of humus in the good soil, and yet we have seen that the chemist may pronounce the cloddy soil richer in native plant-food. If the farmer has much of this hard, unproductive land, what is to be done with it? To cover it with commercial fertilizer would be of little benefit. It must first be put in fit condition for the growing of crops. A crop of clover plowed under would quickly improve it, but if the land is planted to orchard he does not care to seed it down. The next recourse is stable manure. Of this, perhaps had to cover the hardest spots.
enough can be For the rest,
catch or cover crops must be used. early tillage, he can sow rye, and plow it under very early in the spring. Now and then he can use a fall crop of sowed corn or oats, or something of the kind. After a time, he may be able to get the land in such condition of tilth as to secure an occasional stand of crimson clover. This practice, continued judiciously for a few years, ought to radically change the character of the land; but all this will be of little avail unless the plowing and cultivation can also be done in a timely and intelligent way. All this will take time and patience. He may wish that there were some short-cut and lazy way of improving this land by making some application of fertilizer to it, but there is not. The most he can do is to slowly bring it into such condition that it will pay to put concentrated fertilizers on it. In short, the first step in the enrichment of unproductive land is to improve its physical condition by means of careful and thorough tillage, by the addition of humus, and perhaps by underdrainage. It must first be put in such condition that plants can grow in it. After that, the addition of chemical fertilizers may pay by giving additional dundant growth. All this means that no amount of penance in the way of applications to the land can ever atone for the sins of poor tillage; ing cannot be done by recipe.
The gist of the whole matter respecting the use of fertilizers is that the grower should experiment with his plantation, adding a little more of this
and a little more of that as he thinks the different trees or the different types of land may need. There is no other way of arriving at this local knowledge except by trying for oneself. If one is observant of the conditions, he will after a time come to have an intuitive sense of what the land probably needs, but he may not be able to tell just why it needs it. In most matters of handicraft in agriculture, the skilled man develops methods and results almost unconsciously. These methods are really founded upon close observation and truthful inductions, but the person can rarely ever impart this particular information to his neighbor. The only general statement, perhaps, which can be made, is that liberal applications of potash and phosphoric acid should nearly always be made to bearing fruit plants, if the grower desires the best results; and he may be able to supply his nitrogen more cheaply by cover crops and tillage than by buying chemicals.