191 1.] Summary of Agricultural Experiments. 145 



has now been carried on over three seasons with the object of ascertain- 

 ing the amount of seed it is economical to use for a one year's ley. 

 The. plots in each trial were seeded down in the barley crop of the 

 preceding - year, and the produce of the plots was cut and made into 

 hay before weighing. The mixtures consisted of Italian Rye Grass, 

 Red Clover, Alsike, and Trefoil, and in some of them Cow Grass, 

 Perennial Rye Grass, and White Clover were added. The amount and 

 cost of the seed used and the resulting crops are shown below : — 



Weight Cost 



of seed of seed Average 



per acre. per acre. crop. 



lb. s. a. tons cwt, 



15 10 7 27 



224 14 7 25 



35i 20 4 25 



17 12 o 27 



The heavy seedings have thus not given so good a return as the 

 lighter seedings. Very little difference could be seen in the appear- 

 ance of the plots after cutting. 



Live Stock, Poultry, and Feeding Stuffs. 



The Feeding Value of Different Varieties of Mangolds (Jour. Agric. 

 Science, Vol. Hi., Pt. 3, September, 19 10). —An investigation into the 

 chemical composition of mangolds, which was begun in 1903 at Cam- 

 bridge University, showed that the Long Red mangold, owing to its 

 high yield and percentage of dry matter, produces about 20 per cent, 

 more dry food per acre than any other variety. At the same time a 

 series of feeding experiments was started in order to discover whether 

 this superiority of the Long Red over the Globes and Tankards would 

 be borne out in practical farming, that is to say, whether the feeding 

 value of any type of mangold is proportional to its percentage of dry 

 matter. The chemical investigation and the earlier feeding trials were 

 noticed in the Journal for October, 1908, p. 538, but this paper contains 

 a complete summary by Prof. T. B. Wood of the whole investigation 

 which has been carried out by him since 1907. 



The points tested were the comparative feeding value of Yellow 

 Globe and Long Red mangolds as constituents of a liberal fattening 

 diet, the comparative feeding value of Golden Tankard and Long Red 

 mangolds, also in a fattening diet, and the comparative feeding value 

 of Yellow Globe and Long Red mangolds for store cattle. Every pre- 

 caution was taken to choose for the experiment animals of uniform 

 weight and capacity for growth, but, in spite of this, it was found 

 that in a single trial the variation among the individual animals receiv- 

 ing the same treatment was far greater than the quantity the experi- 

 ment sought to measure, and Prof. Wood remarks that little reliance 

 can be placed on the results of single experiments with the small 

 number of animals commonly employed in feeding tests. The results 

 of all the trials are discussed according to the methods used in the 

 theory of probabilities in order to find which of the results obtained 

 were really significant of some difference in the feeding value of the 

 mangolds, and not due to variations in the capacity of the animals for 

 improvement, and the following conclusions are arrived at : — 



L 



