1908.] 



PUBLIC DOCUMENT — No. 33. 



45 



Average Yields per Acre. 



It will be noticed that the combination of fertilizers repre- 

 senting the special corn fertilizer gives an average yield of 

 sound corn at the rate of about 4% bushels per acre more than 

 plots 2 and 4. The yield of soft corn and of stover is, however, 

 larger on plots 2 and 4. We have here an illustration of the 

 well-known effect of a lil)eral supply of solul)le phosphoric acid 

 in hastening, maturity, — an effect which was especially im- 

 portant during the past season, on account of the cold and rainy 

 spring and the low average summer temperature. The greater 

 weight of stover (field cured) on plots 2 and 4 may be in part 

 a consequence of the fact that the crop was not so fully ma- 

 tured, although it has been repeatedly noted in our experiments 

 that a liberal supply of potash promotes a heavy yield of forage. 

 The addition of the basic slag meal to plot 4 has produced no 

 apparent benefit during the past season. 



V. — South Corn Acre. — Manure Alone v. Manure and 



Potash. 



The objects in view in this experiment and the general plan 

 are stated in the following quotation from my last annual re- 

 port : — 



The object in view in this exjieriment is to compare the crop-producing 

 capacity of niamire alone applied in fairly liberal amounts with a com- 

 bination of a lesser amount of manure and a moderate quantity of a potash 

 salt. An acre of land is used in the experiment. It is divided into four 

 plots, of one-quarter acre each. Two of the plots (1 and 3) have received 

 applications of manure only ; the other two plots (2 and 4) have been 

 fertilized by ajiplications of lesser amounts of manure, together with a 

 potash salt. 



This experiment was begun in 1891. The crop for the first six years 

 was corn. Corn was raised also in 1899 and 1900, and in 1903 and 1904. 

 The field has been put into mixed grass and clover three times, being 

 seeded in the summer preceding the first year of cutting in the corn crop. 



