During the spring and fall season agents traverse the state and sample the bags of fertilizers as found on sale by local merchants. The samples are sent by number under seal to the designated chemist, while at the same time the agent transmits to the state officer in charge of the enforcement of the law the necessary information concerning these samples. Upon the receipt of the analysis made by the chemist, who has had no knowledge of the origin of the sample, the state officer compares them with the guarantee of the manufacturer, and if he finds it necessary enters legal complaint. While these laws have been in force for many years in some states and in many states for some years, prosecution has seldom been found necessary. The honest manufacturer is protected from dishonest competition, and the dishonest manufacturer, if there be such, cannot afford the publicity which noncompliance with the law would entail.
It has been customary to publish, with the results of analysis, also an estimate of the commercial value per ton of each brand of fertilizer. This estimated commercial value is obtained by multiplying the pounds of each element or combinations of the element in a ton by a value per pound. To the value of the fertilizer thus obtained is added something for cost of mixing, bagging and freight, and something for profit. The price per pound given to each element or combinations of the elements is based upon the commercial value of the element when purchased in raw materials. The price for each year is usually determined by a conference of those in control of the execution of the law in the several states for certain groups of states. As a matter of fact, the price varies little from year to year.
The published figures, therefore, constitute a table of comparative commercial values as determined by the most expert knowledge. While not constituting a statement of absolute commercial value for any given locality, they do enable the purchaser to determine whether the price quoted on a given brand of fertilizer is within reason. Persons who are unacquainted with the principles controlling the use of commercial fertilizers may, however, be led to believe that the price of the fertilizer is an indication of its value for the production of a given crop. As is well known to all students of the subject, there is no necessary relation between the commercial value of a fertilizer and the fitness of its formula for a given soil and crop. For these and other reasons, the publication of tables of commercial value has been strongly opposed by some manufacturers, and in certain states the custom has been discontinued. While granting that tables of commercial value are subject to misinterpretation, it is perhaps fair to say that such tables have been of most benefit, and, moreover, have been of great value to those who were most likely to misinterpret them.
