216 ANNUAL REPORT OF THE Off. Dnc. 



all the information necessary and thai there is no reason in the 

 nature of the process why they should not ultimately produce as 

 effective cultures as those sent out by the Department. As far 

 as our examinations have, gone of any cultures prepared according 

 to the Department dry culture method, we have had no reason to 

 believe that this culture work is not being properly done. The patent 

 which the Department holds on the method of growing and distrib- 

 uting the bacteria prevents anyone from obtaining a monopoly and 

 it is likely that by another season there will be a considerable addi- 

 tion to the list of firms offering these cultures for sale. By competi- 

 tion, therefore, the cost to the farmer or gardener will undoubtedly 

 be much lessened and the wisdom of the Department's course in 

 patenting the method is already demonstrated. Thus the benefits 

 of the discovery will be brought within the reach of all, whose soil 

 conditions call for artificial inoculation. 



Before investing extensively, however, in any new method for 

 increasing crop yields, whether bacterial or of a different nature 

 each man should determine by small experiments its value for his 

 peculiar needs, and not be unduly influenced by results obtained 

 perhaps under widely differing conditions. 



The CHAIR: No. 2 on the program will now be taken up. "The 

 Proper Theory of Farm Fertilization," by Prof. Wells W. Cooke, 

 Washington, D. C. 



Prof. Cooke's paper is as follows: 



THE PROPER THEORY OF FARM FERTILIZATION. 



By Pkok. Wells W. Cooke, Washington. V. V. 



The answer to the question of the proper theory of farm fertiliza- 

 tion has been given in various ways by different speakers and writers. 

 The one to be given here is based on the idea that no theory of farm 

 fertilization is correct unless its teaching can be followed year after 

 year and generation after generation, and the soil still remain in 

 excellent condition for the production of large crops. But before 

 proceeding to the enunciation of this theory, it will be well to con- 

 sider some of the theories that have been popular and are still 

 heard from the lecture platform. Most of these theories are based 

 on the idea that we should aim to find out what plant food is in the 

 soil, what elements are most lacking, and then supply this deficiency. 

 All agricultural soils contain large quantities of plant food. A fair 

 average for a good soil in the upper foot per anre is abowt 8,000 



