191 1.] Summary of Agricultural Experiments. 675 



in green than tares. It is now proposed to vary the experiment by 

 growing the green crops as before, but feeding them on the land to 

 sheep instead of turning them in green. 



Use of Lime (Rept. on the Woburn Field Expts., Jour. Roy. Agric. 

 Soc, Vol. 71, 1910). — The crop grown on "Butt Furlong" in ia,iowas 

 wheat. This was sown on November 13th, 1909, and a dressing of 

 10 cwt. ground lime per acre was given to one plot on November 23rd. 

 This is the second dressing of 10 cwt. ground lime applied to this plot, 

 the first having been given in the autumn of 1907. A second plot 

 under the experiment was given 2 tons per acre of lump lime in 1907, 

 and has received nothing further. 



The yield from the application of ground lime was 4 bush, more 

 per acre of wheat than on the plot treated in 1907 with 2 tons per 

 acre of lump lime. This latter application, however, gave in 1908 

 io| bush, more of barley than the ground lime, so that there still 

 remains a balance in favour of the lump lime. 



Experiments with Nitrogenous Top-dressings {Rept. on the Woburn 

 Field Expts., Jour. Roy. Agric. Soc., Vol. 71, 1910). — Top-dressings of 



1 cwt. sulphate of ammonia per acre and of calcium cyanamida, cal- 

 cium nitrate, and nitrate of soda, in such quantities as to supply as 

 much nitrogen as that contained in 1 cwt. sulphate of ammonia were 

 given in 19 10 to oats and mangolds. In addition, 3 cwt. mineral super- 

 phosphate per acre was given to the land under oats, and a dressing 

 of 12 tons dung, 3 cwt. superphosphate, 1 cwt. sulphate of potash, and 



2 cwt. salt per acre to the land under mangolds. 



The results in the case of oats confirmed those of the previous year, 

 viz., that when the same amount of nitrogen is applied to corn crops 

 it does not matter much in which form of these nitrogenous top- 

 dressings it is given. 



With the mangold crop sulphate of ammonia was less beneficial 

 than the other three nitrogenous manures. 



In order to ascertain the residual manurial value of these nitro- 

 genous manures, wheat was grown in 19 10 on plots which in 1909 

 were under mangolds and had received the same manures as those 

 stated above to have been given to mangolds in 19 10. Nitrate of soda 

 and sulphate of ammonia were found to leave no residue, but gave 

 rather a lowering of the produce compared with a plot on which no 

 nitrogenous top-dressing had been given in 1909. Calcium cyanamide 

 and calcium nitrate gave a small increase, possibly due to the lime 

 supplied by them, but Dr. Voelcker remarks that there is nothing at 

 present to lead one to think that, in regard to the new nitrogenous 

 manures, their lasting effect requires to be taken into serious con- 

 sideration. 



The Woburn Pot-Culture Experiments, 1909 {Jour. Roy. Agric. Soc, 

 Vol. 71, 19 10). — The Woburn pot-culture experiments of 1909 dealt 

 with the influence of salts of various metals on cereals, the influence of 

 lime and magnesia in different forms on wheat, the influence of lime 

 on a soil rich in magnesia, the influence of magnesia on clover and 

 beans, green manuring experiments, experiments with nitrogenous 

 top-dressings, and experiments on the inoculation of crops. 



From the experiments with lithium and caesium, which have now 



