which determine the farmer's plant food deficiencies. For certain farmers in the Connecticut Valley, whose alluvial soils cry out for potash, to buy the same fixed formula as the Maine farmer, whose granitic soil is, by the processes of weathering, yielding its annual quota of available potash, or for the grain producer, whose environment admits of the successful use of clover in the rotation, to purchase as much nitrogen as the farmer located where clover does not thrive, is to adopt a "rule of thumb" method that does not belong to the highest order of farm management. I grant, yes, I do more than this, I assert, that with the horticulturist, who is engaged in intensive production, the case is different. In the forcing house and garden, conditions are almost if not entirely artificial, so far as it is a question of feeding the plant. Even in the garden, the variations in the natural food supply are obscured by the greater amount of available material supplied by the generous applications of stable and commercial manures. While we must still depend to an extent upon the chemical activities whose field of action is the rich garden loam and the artificial soil of the forcing house, we are comparatively independent of those processes of weathering which are of so much importance as a means of fertility in the long rotations of the grass and grain farm. In the production of grass, grain, and even the ordinary hoed crops, the natural capacity of the soil, or its annual contribution of available plant food is an important, and even a controlling, factor; but in certain lines of horticultural work it is a minor factor. In horticulture and the forcing of vegetables, the plant is the one thing to be considered, and after we have made the physical conditions and water supply what they should be, we may safely proceed to feed the plant as if its sole supply of nourishment is what we furnish it. The considerations stated in the foregoing lead me to the conviction then that the fertilizers ordinarily found in the markets are not economically adapted to certain lines of horticultural work. The proportions of ingredients in these goods is such that it is necessary to purchase too much of one in order to obtain enough of others. For use under the conditions to which I have so far confined this discussion, I am convinced that on the average the amount of phosphoric acid used should at least not be in excess of either the nitrogen or potash, or, in other words, for market garden and forcing house use, the proportions of nitrogen and potash should be greater than is found in the established brands of mixed fertilizers now offered in the market. This desirable change can be secured, as I have already indicated, by the purchase of chemicals to be mixed at home, or by coöperating with some manufacturer in whom you have confidence. Under right conditions either method may be successful. It would be foolish to ignore the manufacturer, because the wisdom of a division of labor holds good here as elsewhere. But we should keep him in his place, which is to supply us with what we wish to purchase, without even supposing that he can determine our needs. These we must discover for ourselves, aided by the investigations and results of others. There has been too much of a feeling on the part of the agricultural public, that somehow or other the manufacturer is able to discern the needs of farmers, because of a higher range of knowledge to which he has access; that somehow or other the same knowledge enables him so to conjure with materials obtained from unusual sources that he is bound to offer, if not the right thing, a very good thing, which rises above the common everyday facts and means of agricultural practice. The crop grower should never forget that the manufacturer is studying commercial opportunities chiefly, and that he is first of all a business man, and is rarely competent either from the practical or scientific standpoint to guide in the practice of plant feeding. His province is to study the markets and processes of manufacture, and in these directions he must lead; but in respect to the use of plant food the farmer should lead, and the manufacturer should buy and manipulate to suit the demand that comes up to him from the consumer. Commercial fertilizers, as they exist in the markets today, are a curious medley. In their composition the fact is recognized that nitrogen, phosphoric acid, and potash, are the three constituents of plant food, one or more of which is likely to be needed to increase fertility; but beyond this they fail in most instances to embody any distinct principle or rule of practice. The so-called special manures of different manufactures, designed for the same crop, differ almost as widely as do the brands designed for general use. Order will sometime come out of this chaos, but chiefly through the efforts of those who use the various preparations of plant food. This will not be done, however, until trade names pass into" innocuous desuetude," and plant food in its various forms, is both bought and sold by the names it properly bears, as one buys and sells sugar, iron, or any other standard commodity. And the time is coming when the general farmer, or the market gardener, will order of the dealer so many pounds each of nitrogen, phosphoric acid, and potash, just as now he purchases seeds and foods. As a suggestion to those, especially market gardeners and those managing forcing houses, who are inclined to mix their own fertilizers or to ask for a definite mixture from the dealer, I offer the following combinations, which may be varied ad libitum. Nitrogen This combination would contain the following: 122 lbs. or 6.1 per cent. Nitrogen This combination would contain the following: 117 lbs. or 5.85 per cent. 66 potash Sulphate of Potash 50 This combination would contain the following: 125 lbs. or 6.25 per cent. Nitrogen Special attention is called to mixture No. 2, which, owing to the low price of cotton-seed meal, would furnish plant food more cheaply than either of the other combinations. It is very easy to see that by varying the quantities of chemicals the mixture may be made to contain more of one ingredient and less of others. Just here the question will arise,-"How shall I know what combination to use?" Only by observation and study. You should not adopt the successful rule of practice of some other man unless your conditions are entirely similar to his. And the only method admitting of intelligent and reliable observation is when fertilizing materials are applied with a full understanding of what they contain, so that it is possible to trace cause and effect. If you purchase these ingredients separately, you are then able to apply them singly, or combined in different forms and in different proportions. In this way you may attain a degree of knowledge applicable to your own business that will never be possible if you continue to buy the fixed formulas of the markets. This may be a hard doctrine, but it is nevertheless the means of salvation. The agricultural public should study carefully the results of experiment station investigations, for in this way much will be learned, which, as general principles, will be important to every man's practice. But never will experiment stations relieve the individual of the necessity of making a close study of the needs and methods of his own environment. the right Principles, the practitioner may be taught by others, relation of the principles to his own business he must, in part at least, discover for himself, and in no field is there a larger opportunity for this than in the purchase and use of commercial fertilizers. DISCUSSION. A gentleman remarked that some persons not familiar with plant culture regard all commercial fertilizers as similar in character to alcohol,― as only stimulants. But the truth is they are really plant food- as positively so as any stable manure. This has been proved by many careful experiments, including those by sand culture and water culture. As no healthy child could be reared on alcohol, so no plant life can be long sustained without being supplied with plant food. William C. Strong asked whether the phosphates of iron and aluminum were undesirable. Professor Jordan replied that for the horticulturist they are; as in his cultural work he had found their action to be too slow. But in farming operations, especially on land about to be laid down to grass, they may be valuable for their staying qualities, as they require much of "Nature's weathering" to develop their useful conditions. Benjamin P. Ware asked what was meant by the terms "available" and "reverted" phosphoric acid. Professor Jordan answered that those expressions represent an important fact. Available phosphoric acid — if such in realityis that which can be rapidly taken up by growing plants. The term "available," as used in connection with fertilizer analysis, means the sum of the water-soluble and reverted (or citrate-soluble). "Reverted" should really be applied only to "that which has once been soluble in water, but by chemical change has gone back;" but is now used in the sense of "that which is soluble in ammonium citrate." The question was asked, What is the relative value of woolwaste and hair-waste as compared with other materials in commercial fertilizers? Professor Jordan replied that although rich in nitrogen, both are very slow to yield their fertilizing elements, unless they are broken down by chemical treatment or some process other than Nature's weathering; even then there are other sources which are preferable for the horticulturist. Cotton-seed meal, for this purpose, is this year sold in Maine at twenty dollars per ton. This yields six and three-fourths per cent of nitrogen; two and threefourths per cent of phosphoric acid, and one and three-fourths per cent of potash. At the price named one can now get a supply of nitrogen from cotton-seed meal more cheaply than from any other source. (In the first two formulas given in the paper read today, the term acid phosphate refers to Florida rock, South Carolina rock, or bone-black, each in a dissolved state.) The next question asked was, What fertilizing elements are derived from bones? To this Professor Jordan replied that bone furnishes phosphoric acid and nitrogen. If bones are steamed, that process takes away a portion of the nitrogenous matter, thus reducing the proportion of nitrogen in the fertilizer. |