agricultural experiment stations and industrial research groups are constantly 

 studying the needs of the soil to improve crop yields. As a result of these studies, 

 other plant nutrients are included in certain fertilizers for specific crops. Mag- 

 nesium and boron are examples of so-called minor elements furnished by some 

 brands of fertilizer to correct specific deficiencies of the soil in certain localities. 



Soil conditioners are materials that have been widely advertised. Their main 

 purpose is to improve soil texture. They may or may not contain added plant 

 food. These materials in themselves supply little or no plant food. They are rela- 

 tively expensive and their use has therefore been limited. There is no accepted 

 method of measuring their relative effectiveness as to whether results as claimed 

 will be obtained. These materials are still in the trial period. They apparently 

 give good results in changing certain soil conditions. 



It is well known that there is much advertising of fertilizer materials directed 

 to the attention of the small home gardener and house plant growers. It is realized 

 that plant food concentrate supplied in small packages has a place. However, 

 certain advertising claims have been open to question. In fact during the past 

 year the American Association of Fertilizer Control Officials issued a warning to 

 the public through the press against "exorbitant and questionable claims" in re- 

 gard to fertilizer materials for home garden and flower production. Generally 

 speaking, it is more economical for the gardener to purchase fertilizer of a re- 

 liable brand and in reasonably large size packages. 



All control officials charged with the enforcement of state laws regulating the 

 sale of commercial fertilizers and fertilizer materials are joined in the Association 

 of American Fertilizer Control Officials. Research workers employed by State or 

 Federal Agencies engaged in the investigation of fertilizers are also members of 

 this Association. The object of this organization is to "promote uniform and 

 effective legislation, definitions, rulings, and enforcement of laws relating to the 

 control of sale and distribution of mixed fertilizers and fertilizer materials in the 

 Continent of North America." Annual meetings of this Association are held at 

 which reports and recommendations of investigators concerning definitions of 

 fertilizer materials, use of new products, and problems concerning regulation of 

 the fertilizer trade are discussed in detail. Fertilizer manufacturers are invited to 

 participate in these discussions and through mutual cooperation the farmer is 

 supplied with a product that can be relied upon to do the job expected in crop 

 production. The official publication of the Association may be obtained for a small 

 fee through the office of its secretary, B. D. Cloaninger, Clemson, South Carolina. 

 This booklet contains the official terms describing fertilizer materials, a proposed 

 model state fertilizer law as well as the proceedings of the annual meeting. 



Whether or not a fertilizer contains the guaranteed amount of plant food 

 can be determined only by a chemical analysis. For this reason it is considered 

 necessary that each brand of fertilizer offered for sale be officially sampled and 

 analyzed each year. When failure to meet the guarantee is proved by chemical 

 analysis, the prosecution or seizure provisions of the law may be invoked. The 

 purchaser's refusal to buy a fertilizer which does not conform to the law will not 

 only assist in the enforcement of the law but will at the same time insure him the 

 protection of the law. 



USE OF COMMERCIAL FERTILIZERS 



It is not within the scope of this department to make recommendations re- 

 garding the use of commercial fertilizers. The Department of Agronomy and the 

 Department of Agricultural and Biological Chemistry of the University of New 

 Hampshire Agricultural Experiment Station test soils and conduct experimental 

 work with various fertilizer materials on hay and crop land. The Department of 

 Horticulture investigates fertilizer treatments for fruits and vegetables. Much of 

 this work has been published, and is available for free distribution to residents of 



