The First Book of Farming

Chapter 26

Chapter 261,740 wordsPublic domain

COMMERCIAL FERTILIZERS--CONTINUED

MIXED FERTILIZERS

_What they are._

There are a large number of business concerns in the country which buy the raw materials described in Chapter XXI, mix them in various proportions, and sell the product as mixed or manufactured fertilizers. If these mixtures contain the three important plant foods, nitrogen, phosphoric acid and potash, they are sometimes called "complete" manures or fertilizers. In some parts of the country all commercial fertilizers are called "guano."

_Many brands._

These raw materials are mixed in many different proportions and many dealers have special brands for special crops. There are consequently large numbers of brands of fertilizers which vary in the amounts, proportions and availability of the plant foods they contain. For instance, in 1903, twenty-three fertilizer manufacturers offered for sale ninety-six different brands in the State of Rhode Island. In Missouri one hundred and ten brands, made by sixteen different manufacturers, were offered for sale. Eighty-three manufacturers placed six hundred and forty-four brands on the market in New York State during the same year. Of one hundred and twenty brands registered for sale in Vermont in the spring of 1904, there were seventeen mixtures for corn and thirty-four for potatoes.

The result of this is more or less confusion on the part of the farmer in purchasing fertilizers, and with many a farmer it is a lottery as to whether or not he is buying what his crop or his soil needs.

Some of the manufacturers are not above using poor, low grade, raw materials in making these mixtures.

This means that the farmer should make himself familiar with the subject of fertilizers if he desires to use them intelligently and economically.

_Safeguard for the farmer._

As a safeguard to the buyer of fertilizers the State laws require that every brand put on the market shall be registered and that every bag or package sold shall have stated on it an analysis showing the amounts of nitrogen, or its equivalent in ammonia, the soluble phosphoric acid, the reverted phosphoric acid, the insoluble phosphoric acid, and the potash.

This registration is generally made at the State experiment station, and the director of the station is instructed to take samples of these brands and have them analyzed, and publish the results together with the analysis guaranteed by the maker.

These analyses are published in bulletin form and should be in the hands of every farmer who makes a practice of using commercial fertilizers.

The manufacturers of fertilizers comply with the law by printing on the bag or package the per cents of plant food in the fertilizers, and these statements in the great majority of cases agree favorably with the analyses of the experiment stations, but they do not in all cases state what materials were used to furnish the different kinds of plant food, and it is not always possible to find this out by analysis.

_Low grade materials._

For instance in mixing a fertilizer one manufacturer may use dried blood to furnish nitrogen and another may use leather waste or horn shavings. The latter contains more nitrogen than the dried blood, but they are so tough and decay so slowly that they are of little benefit to a quick growing plant.

_Inflating the guarantee._

Although the dealer states correctly the per cents of plant food in the fertilizer, he is quite frequently inclined to repeat this in a different form, and thus give the impression that the mixture contains more than it really does.

The dealers also give the nitrogen as ammonia because it makes a larger showing.

Phosphoric acid is often stated as "bone phosphate" because in this the amount appears to be greater.

For example, an analysis taken from a fertilizer catalogue reads as follows:

Ammonia 2 to 3 per cent. Available Phosphoric Acid 8 to 10 " Total Phosphoric Acid 11 to 14 " Total Bone Phosphate 23 to 25 " Actual Potash 10 to 12 " Sulphate of Potash 18 to 20 "

A better statement would be as follows:

Nitrogen 1.65 per cent. Available Phosphoric Acid 8 " Total Phosphoric Acid (furnished in Bone Phosphate) 11 " Potash (furnished in Sulphate of Potash) 10 "

Ammonia is reduced to terms of nitrogen by multiplying by .824. All bone phosphate is forty-six per cent. phosphoric acid. When bone phosphate is given instead of phosphoric acid it simply makes the mixture appear to have more in it, and when both phosphoric acid and bone phosphate are stated one is merely a repetition of the other. The same is true of the statements, potash and sulphate of potash, one is a repetition of the other only a different form.

VALUATION

The experiment stations not only publish comparative analyses of the registered fertilizers but they also compute the market values of the plant food contained in them and compare these valuations with the selling price of the fertilizers.

They also furnish a list of trade values of the plant foods in raw materials for the convenience of fertilizer buyers in testing the values of the brands offered them on the markets.

In the following list are given the "trade values agreed upon by the Experiment Stations of Massachusetts, Rhode Island, Connecticut, New Jersey and Vermont, after a careful study of prices ruling in the larger markets of the southern New England and Middle States."

Trade values of fertilizing ingredients in raw materials and chemicals for 1904:

Cents per lb. Nitrogen in Nitrates 16 Nitrogen in Ammonia Salts 17½ Organic Nitrogen in dry and fine ground fish, blood, and meat, and in mixed fertilizers 17½ Organic Nitrogen in fine ground bone and tankage 17 Organic Nitrogen in coarse bone and tankage 12½ Phosphoric Acid soluble in water 4½ Phosphoric Acid soluble in ammonium citrate 4 Phosphoric Acid in fine ground bone and tankage 4 Phosphoric Acid in coarse bone and tankage 3 Phosphoric Acid (insoluble in water and in ammonium citrate) in mixed fertilizer 2 Potash as high-grade sulphate and in mixtures free from muriate (chloride) 5 Potash as muriate 4¼

For example, in calculating the commercial value of the plant food in a fertilizer we will take the formula mentioned on page 205, namely:

Ammonia 2 to 3 per cent. Available Phosphoric Acid 8 to 10 " Total Phosphoric Acid 11 to 14 " Total Bone Phosphate 23 to 25 " Actual Potash 10 to 12 " Sulphate of Potash 18 to 20 "

This fertilizer is evidently a mixture of bone meal and sulphate of potash and the plant food contained in it is as follows:

Nitrogen 1.65 per cent. Available Phosphoric Acid 8 " Insoluble Phosphoric Acid 3 " Potash 10 "

One hundred pounds of the mixture would contain:

Pounds. Value per 100 lbs. Nitrogen 1.64 value at 17½¢ .29 Available Phosphoric Acid 8 " " 4¢ .32 Insoluble Phosphoric Acid 3 " " 2¢ .06 Potash 10 " " 5¢ .50 ----- Total $1.17

In one ton the whole value would be twenty times this or $23.40. Add to this $8, which is about the average charge for mixing, bagging, shipping, selling and profit, and we find that $32 is probably the lowest figure at which this fertilizer could be purchased on the markets, and very likely the price would be higher as we have taken the lowest guaranteed per cent. of plant food for our basis of calculation.

Fertilizers are generally mixed and sold to the farmer on the ton basis.

LOW GRADE MIXTURES

Most dealers, to meet a certain demand, furnish mixtures ranging from $15 to $25 per ton. These mixtures are necessarily low grade and are more expensive than the higher priced high grade mixtures.

For example:

A certain potato fertilizer on the market, which we will call mixture A, has the following guaranteed analysis:

Ammonia 7 to 8 per cent. Available Phosphoric Acid 6 to 7 " Actual Potash 5 to 6 "

A ton of this would contain:

Pounds. Nitrogen 115.4 value at 17½¢ $20.19 Available Phosphoric Acid 120 " " 4¢ 4.80 Potash 100 " " 5¢ 5.00 ----- ------ Totals 335.4 $29.99

Add to this the average charge for mixing, bagging, selling, profit, etc., $8, and the cost will be $37.99.

The selling price of this fertilizer would probably be not less than $40. Now suppose the farmer thinks this a high priced and expensive fertilizer and looks about for something cheaper. He finds a low grade potato fertilizer, which we will call mixture B, that has the following guarantee:

Ammonia 3½ to 4 per cent. Available Phosphoric Acid 3 to 3½ " Actual Potash 2½ to 3 "

Just one-half the guarantee of the high grade mixture A. A ton of this contains:

Pounds. Nitrogen 57.7 value at 17½¢ $10.10 Available Phosphoric Acid 60 " " 4¢ 2.40 Potash 50 " " 5¢ 2.50 ----- ------ Totals 167.7 $15.00 Add average charge for mixing, etc. 8.00 ------ $23.00

The selling price of this would very likely be not less than $25.

This seems at first sight to be cheaper and more reasonable. But let us see.

In a ton of mixture A he gets 335.4 pounds of plant food for $40, or at an average cost of twelve cents per pound, while in a ton of mixture B he gets 167.7 pounds of plant food for $25, or at an average cost of fifteen cents per pound.

To put it another way, in a ton of the high grade mixture A, he gets 335.4 pounds of plant food for $40. To get the same amount of plant food, 335.4 pounds, in the low grade mixture, B, it will be necessary to buy two tons at a cost of $50.

A low grade fertilizer is always expensive even if the plant food is furnished by high grade materials.

BUY ON THE PLANT FOOD BASIS

The farmer generally buys his fertilizer on the ton basis. A better method is to buy just as the fertilizer manufacturers buy the raw materials they use for mixing, namely, on the basis of actual plant food in the fertilizer. The dealers have what they call the "unit basis," a "unit" meaning one per cent. of a ton or twenty pounds of plant food. A ton of nitrate of soda, for instance, contains 310 pounds or 15½ units of nitrogen, which at $3.20 cents per unit would cost $49. Buy your mixture of a reliable firm, find out the actual amounts of the plant foods in the mixture and pay a fair market price for them.