1904.] PUBLIC DOCUMENT — No. 33. 143 



soil. To Plot 10 dissolved bone-black has been added, as 

 well as the nitrate of soda and muriate of potash, and this, 

 because of the lime it contains, has helped to lessen the ten- 

 dency to the development of acidity ; but even on this plot 

 the yield is less than on the nitrate of soda alone, and prob- 

 ably because of the acid condition induced by the continued 

 use of the fertilizers the plot has received. 



A careful determination of the relative proportions of the 

 timoth}', red-top and clover in the product of a square yard 

 on both the unlimed and limed portions was made. On the 

 unlimed portion of every plot the red-top was more abun- 

 dant than the timothy. There was practically no clover on 

 the unlimed portion of any plot. Timothy exceeded red- 

 top on the limed portion of all plots except Plot 7. This is 

 the plot to which both the nitrate of soda and muriate of 

 potash have been applied ; and here, in spite of the lime Avhich 

 was put on in 1899, the soil is undoubtedly again acid, as 

 shown by the fact that the red-top exceeds the timothy. 

 Clover was found in appreciable quantities only on the limed 

 portion of plots 9 and 10. The lessons of the experiment, 

 it seems to me, are clear, the following being the most im- 

 portant points : — 



1. Nitrate of soda, as in many previous experiments, 

 proves the controlling element in the production of grass ; 

 but this exerts the full eft'ect of Avhich it is capable only on 

 soils which are not excessively acid. 



2. Whenever, in a mowing seeded with a mixture of 

 timothy and red-top, the latter largely predominates, it is an 

 evidence that the productivity of the field would be increased 

 by an application of lime. 



3. Clover cannot be made to thrive in a soil unless it is 

 free from acidity ; and in those cases where on seeding clover 

 foils, acidity may reasonably be looked for. 



VII. — Experiment in Manuring Grass Lands. 



In this experiment, which has continued since 1893, the 



purpose is to test a system of using manures in rotation for 



the production of grass. The area used in the experiment 



is about nine acres. It is divided into three approximately 



