Crops and Methods for Soil Improvement Part 10

The prices named would seem high to good cash buyers near the seaboard, and they are too low for some other regions where freights are very high. They are only ill.u.s.trative. The consumer can get his own basis for an estimate by obtaining the best possible cash quotations from city dealers. Some interested critic may point out that nitrate of soda should not be the sole source of nitrogen in a fertilizer on account of its immediate availability. Manufacturers use some sulphate of ammonia, and a pound of nitrogen in it has had practically the same market price as that in nitrate of soda. Tankage may be used in part, and in it the nitrogen costs very little more per pound.

It may be said that the potash in the fertilizer is in form of sulphate. Usually that profits the user nothing, and often the claim is baseless, but if it is a sulphate, the cost of the potash should have only 20 per cent added to the valuation of the potash, which usually will not add one dollar to the total cost of the ton of mixed fertilizer. Basing the valuations of the pounds of plant-food in the mixed fertilizer on the value per pound in unmixed materials delivered to one's own locality, there must be taken into account the added expense of mixing.

High-grade Fertilizers.--A high-grade fertilizer is not necessarily a high-priced one. What we want in a fertilizer is a high content of the plant-food needed, together with desirable availability. If only phosphoric acid is wanted, a 14 per cent, or 16 per cent, acid phosphate is high-grade because it contains as many pounds of available phosphoric acid in a ton as the public can buy in a large way. A 10 per cent acid phosphate is low-grade. The effort is to escape paying freight, and other cost of handling, on waste material as far as possible. Generally speaking, the higher the percentages of plant-food in a fertilizer, the cheaper per pound is the plant-food. A low-grade fertilizer rarely fails to be an expensive one because the expense of handling adds unduly to the price per pound of the small content of plant-food.

CHAPTER XIX

HOME-MIXING OF FERTILIZERS

The Practice of Home-mixing.--The business of compounding fertilizers has been involved in a great deal of unnecessary mystery. Many of our best station scientists have labored to show that the home-mixing of fertilizers is a simple and profitable piece of work, and the heaviest users of fertilizers in the east now buy unmixed materials, but a majority of farmers use the factory-mixed. Manufacturers are right in their contention that many people do not know what materials are best for their own fields, or what proportions are best, but the purchase of mixed materials does not solve their problem and it does not help them to a solution as quickly as home-mixing. The source of the plant-food in the factory-mixed goods is not known, while it is known in the home-mixed.

Effectiveness of Home-mixing.--Van Slyke says ("Fertilizers and Crops,"

p. 477): "Manufacturers of fertilizers and their agents have persistently sought to discourage the practice of home-mixing, but their statements cannot be accepted as the evidence of disinterested parties. It has been represented to farmers that peculiar and mysterious virtues are imparted to the plant-food const.i.tuents by proper mixing, and that really proper mixing can be accomplished only by means not at the command of farmers. Such statements are misrepresentations, based either upon the ignorance of the person who makes them or upon his determination to sell commercial mixed goods."

Criticisms of Home-mixing.--The manufacturer's advocate formerly laid much stress upon the danger attending the treatment of bones and rock with sulphuric acid. That is a business of itself, and the home-mixer has nothing to do with it. He buys on the market the acidulated bone or rock, just as a manufacturer makes his purchase.

It is claimed that the manufacturer renders a great public service by using supplies of plant-food that the home-mixer would not use, and thus conserves the world's total supply. Let us see the measure of truth in the statement. The manufacturer gets his supply of phosphoric acid from rock, bone, or tankage exactly as does the home-mixer. His potash he buys from the syndicate owning the German beds, and the farmer does the same. These sources must contribute all the phosphoric acid and potash used on land, if we except trifling supplies of ashes, marl, etc., and the only difference in the transaction is that in one case the manufacturer buys the materials and mixes them, and in the other case the farmer buys them direct and mixes them. The remaining const.i.tuent is the nitrogen. If the manufacturer uses nitrate of soda, sulphate of ammonia, bones, tankage, or manufactured nitrogen, he does what the home-mixer may do. Most nitrogen must come from these sources.

If all came from these sources, the increased demand would not affect the price. The beds of nitrate of soda will last for hundreds of years, the present waste in ammonia from coal is immense, and the supply of manufactured nitrogen can be without limit. The saving in use of inert and low-grade forms of nitrogen is more profitable to the manufacturer than to the farmer who buys and pays freight on low-grade materials.

The rather remarkable argument is advanced that fertilizer manufacturers do not make a large per cent on their investment, despite the perfection of their equipment, and therefore the farmer cannot find it profitable to mix his materials at home. By the same reasoning, a.s.suming for the moment that the profit in manufacturing does not pay a heavy dividend on all the stock issued, if a great hotel does not find its dining-room a source of profit, as many hotels do not, no private home should hope to prepare meals for its own members in compet.i.tion with hotels.

As has been stated, every user of commercial fertilizer should learn what a pound of plant-food in unmixed material would cost him, selecting the common materials that are the only chief sources. If he can buy a pound of nitrogen in nitrate of soda or sulphate of ammonia, a pound of phosphoric acid in acid phosphate or steamed bone, and a pound of potash in muriate or sulphate of potash for less than they would cost in the factory-mixed goods offered him, allowing to himself a dollar or so a ton for the labor of mixing, it is only good business to buy the unmixed materials. The saving usually is from five to ten dollars a ton, excepting only interest on money, as he would pay cash for the unmixed material.

The cost of bags always is mentioned. That is not to be considered by the farmer, as he uses the bags in which the unmixed materials come to him.

The Filler.--There has been much misleading use of the word "filler,"

as applied to fertilizers. We have seen that a pure grade of dried blood contains about 13 per cent of nitrogen. The buyer of a ton of dried blood thus gets about 260 pounds of plant-food. The remaining 1740 pounds const.i.tute what may be called nature's "filler." The blood is a good fertilizer. We do not buy nitrogen in a pure state. We buy a ton of material to get the needed 260 pounds of nitrogen. Thus it is with nitrate of soda, sulphate of ammonia, acid phosphate, muriate and sulphate of potash, and all other fertilizer materials. As freight must be paid upon the entire ton, it usually pays best to select materials that run high in percentage of plant-food. It is possible to get very low-grade fertilizers that have not had any foreign material added by the manufacturer. An acid phosphate may be poor in phosphoric acid because low-grade rock was used in its manufacture. Kainit is a low-grade potash because the impurities have not been taken out. Filler may be used, however, for two reasons, and one is legitimate. When limestone or similar material is used merely to add weight, reducing the value per ton, the practice is reprehensible. The extent of this practice is less than many suppose, preference being given to the use of low-grade materials in making very low-priced fertilizers.

A legitimate use of filler is to give good physical condition to a fertilizer. Some materials, such as nitrate of soda and muriate of potash, take up moisture and then become hard. The addition of peat or limestone or other absorbent is necessary to keep the ma.s.s in condition for drilling. The use of some steamed animal bone or high-grade tankage in the mixture helps to prevent caking. The home-mixer can use a drier without loss, as he does not pay freight upon it. Dry road dust will serve his purpose. His need of a drier may be greater than that of the manufacturer, as he probably will use only high-grade unmixed materials. If the use of the home-mixture is immediate, no drier to prevent caking is needed, but its presence facilitates drilling.

Storage of unmixed materials in a dry place is an aid in maintaining good condition.

Ingredients in the Mixture.--The matters of interest to the farmer are the determination of the amounts of nitrogen, phosphoric acid, and potash that he should apply to a particular field, their availability, and their cost. Let us a.s.sume that he has found 300 pounds of a fertilizer containing 3 per cent nitrogen, 10 per cent phosphoric acid, and 6 per cent potash to be an excellent application for wheat on a thin soil that is to be seeded to clover and timothy. This fertilizer contains 3 pounds of nitrogen to each 100 pounds. He applies 300 pounds of the fertilizer per acre, or 9 pounds of nitrogen. The fertilizer contains 10 pounds of phosphoric acid to the 100 pounds. He thus applies 30 pounds of phosphoric acid per acre. The fertilizer contains 6 pounds of potash per 100 pounds, and he therefore applies 18 pounds per acre. What he has really learned, then, is that an acre of this land, when seeded to wheat, needs 9 pounds of nitrogen, 30 pounds of phosphoric acid, and 18 pounds of potash. It is in these terms he should do his thinking, and the matter of fertilization becomes simple.

In the general farming of the Pennsylvania experiment station, it is the practice to depend upon nitrate of soda as the source of a fertilizer for wheat. Manufacturers claim that sulphate of ammonia and tankage would be better. The farmer soon will learn what he prefers for his soil, provided he practices home-mixing.

Let us a.s.sume that he uses nitrate of soda, which never varies much from 15 per cent in its content of nitrogen. If 100 pounds of nitrate contain 15 pounds of nitrogen, the 9 pounds wanted for an acre will be found in 9/15 of 100 pounds or 60 pounds.

Thirty pounds of phosphoric acid are wanted for an acre. If the acid phosphate contains 14 per cent of phosphoric acid, or 14 pounds to the 100, the required amount will be 30/14 of 100, or 214 pounds.

Eighteen pounds of potash are wanted for an acre. The muriate of potash on our markets never varies much from 50 per cent in its content of potash. If 100 pounds of muriate contain 50 pounds of potash to the 100, the required amount wanted will be 18/50 of 100, or 36 pounds.

Adding the 60, 214, and 36 pounds, we have 310 pounds for the acre of land. If the field contains 20 acres, the order will call for 20 times the 60 pounds of nitrate of soda, 20 times the 214 pounds of acid phosphate, and 20 times the 36 pounds of potash.

If the farmer prefers to use sulphate of ammonia, which varies little from 20 per cent of nitrogen, or 20 pounds in the 100, he will get his 9 pounds of nitrogen for an acre by buying 9/20 of 100 pounds, or 45 pounds, and the subst.i.tution of the 45 pounds of sulphate of ammonia for the 60 pounds of nitrate of soda will reduce the total application of fertilizer per acre from 310 pounds to 295 pounds. The important fact is that in either case there is the required amount of nitrogen.

Let us a.s.sume that the field contains enough nitrogen, but other needs remain the same. In such case, the nitrogen is dropped out, and the application becomes 250 pounds per acre.

The home-mixer may subst.i.tute tankage of guaranteed a.n.a.lysis for part of the nitrogen and phosphoric acid. Let us a.s.sume that the tankage runs 9 per cent nitrogen and 20 per cent phosphoric acid. If half the required nitrogen per acre, or 4-1/2 pounds, is wanted in tankage, 50 pounds of the tankage will supply it. At the same time the 50 pounds of tankage supplies 10 pounds of phosphoric acid, replacing one third of the 214 pounds of acid phosphate. We thus have for the acre 30 pounds of nitrate of soda, 50 pounds of tankage, 143 pounds of acid phosphate, and 36 pounds of potash, or 259 pounds. The content of plant-food remains the same, but one half of the nitrogen is only slowly available. The farmer who buys unmixed materials will incline to use only a few kinds, and at first he will confine himself chiefly to materials whose composition varies little. In this way he quickly sees in a ton of the material, not the whole bulk, but the definite number of pounds of nitrogen and other const.i.tuents of plant-food contained in it, and the calculations in home-mixing become simple.

Materials that should not be Combined.--The advocate of factory-mixed goods warns the farmer against the danger of making combinations of materials that will cause loss by chemical action. The danger is wholly imaginary if no form of lime, wood-ashes, or basic slag is used in the home-mixtures. As has been said, some materials will harden, if permitted to absorb moisture, and if the mixture must stand, a few hundred pounds of muck or dry road dust should be added to each ton as a drier, and a correspondingly larger amount per acre should be applied.

Making a Good Mixture.--The process of mixing is simple, and careful station tests have shown that it is fully as effective as factory-mixing. The unmixed materials should be kept in a dry place until the mixing is done. If there are any coa.r.s.e lumps, a wooden tamper can crush them on the barn floor, and the material should be pa.s.sed through a sand-screen. The material of largest bulk should be spread on the floor, and the other materials should be put on in layers. Three careful turnings with a shovel will secure good mixing.

Scales should be used to secure accuracy in desired amounts of the materials.

Buying Unmixed Materials.--Acid phosphate, animal bone, and tankage can be bought of any fertilizer agent, but when one pays cash, he does well to get quotations from various leading manufacturers. The names of dealers in nitrate of soda can be secured from the New York agency which keeps its address before the public in agricultural papers. This is likewise true in the case of the syndicate controlling all the potash. When the addresses of leading distributors of all needed materials have been secured, quotations should be obtained on a cash basis. The best terms are obtained by groups of men combining their orders.

CHAPTER XX

MIXTURES FOR CROPS

Composition of Plant not a Guide.--It has been pointed out that a chemical a.n.a.lysis of a soil is not a dependable guide in the selection of a fertilizer. Years ago the theory was advanced that the a.n.a.lysis of the crops desired should be a guide, but it has proved nearly worthless. This theory does not take into account the soil's supply of plant-food. Moreover, a certain crop may demand a large supply of an element at a time of the year when the soil's supply is inactive. The need of nitrogen for gra.s.s in the early spring, before nitrification in the soil is active, is an ill.u.s.tration. Let the causes be what they may, the fertilizer formulas that call for plant-food in a fertilizer in the same proportions that it is found in plants are disappointing in their results. The a.n.a.lysis of the plant is not a dependable index.

The Multiplication of Formulas.--Fertilizer manufacturers have made all possible combinations of fertilizer materials, using them in various quant.i.ties. Each manufacturer has given a mixture a brand of his own, and confusion reigns. There is no formula for a soil or crop that will remain absolutely the best, even for one particular field. It represents one's judgment of the present need, and is employed subject to change, just as is the prescription of a physician. It is usually only an approach toward the most profitable amount and kind of plant-food that may be supplied. The one important consideration is that no manufacturer can know the need nearly so well as the intelligent farmer who knows the history of his field and constantly tests its ability.

[Ill.u.s.tration: On the productive farm of Dr. W. I. Chamberlain, in Northern Ohio.]

A Few Combinations are Safest.--It is the best judgment of scientists to-day that greater results would be obtained from the use of commercial fertilizers if the number of formulas could be reduced to ten, or even a less number. The satisfactory fertilizers fall into three cla.s.ses:

1. The phosphatic fertilizer, carrying phosphoric acid to land that gets its nitrogen from clover or stable manure, and that continues to supply its own potash. Such a fertilizer should have a high content of phosphoric acid in order that the freight charge, per pound of plant-food, may be as low as possible. Acid phosphate, basic slag, and bone are chief in this group.

2. The combination of phosphoric acid and potash that is needed by soils obtaining all required nitrogen from clover or manure. In most instances the phosphoric acid should run higher than the potash, but the percentage of potash should never run lower than 4.

A lower percentage of potash is not as profitable as a higher one, provided any potash is needed. The potash content should be greater than that of the phosphoric acid in case of some sandy soils and of some crops of heavy leaf growth, including various garden crops.

3. The so-called "complete" fertilizer that supplies some nitrogen with the two other plant-const.i.tuents. Such fertilizer should furnish, with few exceptions, 3 per cent of nitrogen, if no more.

Amount of Application.--In common practice fertilizers are not applied freely enough when they are used at all. The exception to this rule may be found in the case of small applications to cold and inert soils to force growth in the first few weeks of a plant's life. It is difficult to see how 80 or 100 pounds of fertilizer can affect an acre of land one way or the other, but experience teaches that such an amount can do so in respect to young plants. Phosphoric acid has peculiar power in forcing some development of roots in a small plant, and a small application in the drill or row may help the plants to gain ability to forage for themselves.

In early spring a small application of nitrate of soda has marked effect, tiding the plants over a period of need until the soil is ready to give up a part of its store.

If a soil is not fertile, and fertilizers are needed as an important source of plant-food throughout the season, the application should be liberal. If it is necessary to plant a field that is deficient in fertility, expending labor and money for tillage and seed, the only rational course is to furnish all needed plant-food for a good yield.

There may be little net profit from the one crop, but there will be more than could be obtained without the liberal fertilization, and the soil will be better equipped for another crop. This applies, in a notable degree, to fertilization of a wheat crop with which timothy and clover will be seeded. The difference in cost of 350 pounds of a high-grade fertilizer and 150 pounds of a low-grade one, when applied to a poor soil under these circ.u.mstances, may be recovered in the grain crop, and at the same time a good sod will be made possible for the permanent improvement of the land. It is a safe business rule that land should be left uncultivated unless enough plant-food can be provided in some way for a good yield. The man who cannot incur a heavy fertilizer bill, when necessary, should restrict acreage for his own sake.

Similarity of Requirements.--Many of our staple crops are very similar in their fertilizer requirements, and this simplifies fertilization.

Setting aside the impression gained from the dissimilarity in the so-called corn, potato, wheat, and gra.s.s fertilizers on the market, the farmer knows that the soil which is in a good state of fertility is best for any of them, and if the soil is hard-run, it should have its plant-food supply supplemented. The hard-run soil usually is lacking in available supplies of all three plant-food const.i.tuents. If a fertilizer containing 3 per cent of nitrogen, 10 per cent of phosphoric acid, and 6 per cent of potash serves the wheat well, it will serve the timothy that starts in the wheat. Likewise it will serve the corn, although a heavier application will be needed because corn is a heavy feeder. Experience has taught that it will serve the potato similarly, and that the potato will repay the cost of free use of fertilizer. If the soil is sandy and deficient in potash, the percentage of phosphoric acid may be cut to 8, and the percentage of potash raised to 10, and all these crops will profit thereby. If the nitrogen content in the soil is high, none of these crops may need nitrogen in the fertilizer.

This is a general principle, and safe for guidance, though the best profit will demand some modification that readily occurs to the farmer as he studies his crops and their rotation. To ill.u.s.trate: The corn is given the clover sod or the manure partly because it requires more plant-food than the wheat. It gets the best of the nitrogen, and may need only a rock-and-potash fertilizer, while the wheat that follows may need some available nitrogen to force growth in the fall. There is no fixed formula for any field or crop, and the point to be made here only is that the requirements of many standard crops do not have the dissimilarity usually supposed, except in respect to quant.i.ty. A marked exception is found in the oat crop, which does not bear the application of much nitrogen, and often fares well on the remains of the manure that fed the corn, if some phosphoric acid is added.

Maintaining Fertility.--A heavy clover sod gives a.s.surance that a good crop of corn or potatoes can be grown. If the amount of plant-food in the sod is not excessive, a heavy crop of wheat can be produced. The condition of the soil favors many crops. The clover has placed it upon a productive basis for the time being.

The object that should be kept in view, when a scheme of soil fertilization is worked out, is the maintenance of such a state of fertility that the land can be depended upon for whatever crop comes round in the rotation. When a 3-10-6 fertilizer, or a 3-8-10 fertilizer, is used, the effect upon a thin soil is to restore it temporarily to this good-cropping power, the size of the application varying with the crop. A richer soil may want the phosphoric acid and potash without the nitrogen. A manured soil may need only the phosphoric acid. The purpose of the fertilizer in any case is maintenance or increase of fertility, and when this object has been secured, the crop may be whatever the rotation calls for. It is this rational scheme that gives success to the Pennsylvania station's methods on some of its test plats. A given amount of plant-food is put upon the land, which is under a four-years' rotation. One half of it is applied every second year. The corn gets one half because it can use it to advantage. The oat crop that follows finds enough fertility because the soil is good. Next in the rotation is the wheat, and the wheat and timothy and clover plants can use fertilizer with profit. There is no change in its character because it is the soil that is getting the a.s.sistance, and not primarily just one crop in a rotation. The land in this experiment that is well fertilized is more productive than it was thirty years ago, although no manure has been applied, and it is the general productive condition that a.s.sures good yields, and not chiefly any one application of fertilizer.

Fertilizer for Gra.s.s.--A fertile soil will make a good sod. A thinner soil should have a liberal dressing of complete fertilizer at seeding time, and the formula that has been suggested is excellent for this purpose. If a succession of timothy hay crops is desired, the problem of maintaining fertility is wholly changed. The nitrogen supplied by the clover is soon exhausted, and the timothy sod must be kept thick and heavy until broken, or the soil will not have its supply of organic matter maintained. Nitrogen must be supplied freely, and phosphoric acid and potash must likewise be given the soil. The draft upon the soil is heavy, and at the same time the effort should be to have a sod to be broken for corn that will produce a big crop without the use of any fertilizer. The gra.s.s is the natural crop to receive the plant-food because its roots fill the ground, and the corn should get its food from the rotting sod, when broken. Station tests have shown that a sod can be caused to increase in productiveness for several years by means of annual applications of the right combinations of plant-food in the early spring. A mixture of 150 pounds of nitrate of soda, 150 pounds of acid phosphate, and 50 pounds of muriate of potash is excellent. This gives nearly the same quant.i.ty each of nitrogen, phosphoric acid, and potash, and is near a 7-7-7 fertilizer. The only material change in relative amounts of plant-food const.i.tuents, when compared with a 3-10-6 and 3-8-10 fertilizer, is in the increase of nitrogen, due to the heavy drafts made by continuous mowings of timothy. This fertilizer should be used as soon as any green appears in the gra.s.s field in the spring after the year of clover harvest. The large amount of nitrogen makes this an unprofitable fertilizer for clover, and its use is not advised until the spring of the year in which timothy will be harvested.