54 



THE MANURING OF GRASS LAND 



[CH. 



Another instance is furnished by the Garforth experiments 1 

 over the 12 year period, 1899-1910. A complete mixture of 

 artificials applied every year gave the highest percentage of good 

 grass, and the lowest percentage of weeds. Cocksfoot and golden 

 oat were strongly encouraged, while bent and sorrel were greatly 

 reduced. The omission of potash only slightly brought down the 

 yield, but affected the quality of the herbage to a greater extent, 

 reducing the proportion of grass, and increasing that of weeds, 

 especially of sorrel: 



* 1| cwts NaN0 3 , 2 cwts superphosphate, 3 cwts kainit per acre. 



Dung encouraged the good grasses, especially foxtail and cocks- 

 foot, and repressed bent, but it also encouraged soft brome a 

 poor grass and very considerably increased the proportion of 

 weeds. 



The Cockle Park experiments 2 led to the same results. 

 Nitrogenous manures increased the crop, but caused deterior- 

 ation in the herbage. When basic slag was supplied in 

 addition there was a larger and much more profitable crop. 

 None of the manures tested, however, were as effective as the 

 combination of dung and artificials 3 , or as profitable as dung. 

 Thus, on the Palace Leas Field the average yields of hay in cwts 

 per acre for the 18 years 1897 to 1914 and the live weight 

 gains per week in sheep fed on equal weights of the hay during 

 the period November, 1905, to January, 1906, were: 



1 Leeds Bull No. 85, p. 5, 1910. 



2 Cockle Park Bull No. 22, 1915. 



3 The dressings were 150 Ibs sulphate of ammonia, 300 Ibs slag (or, in some of 

 the earlier years, 400 Ibs super.), 100 Ibs muriate of potash per acre. 



