CH. xj Time of Application 185 



ing. On the other hand there seems to be less loss where 

 the clung is only applied once in four years as in ordinary 

 farming, and where proper rotations and well-balanced 

 manurial schemes are adopted. The cause of the loss is 

 being investigated at Rothamsted. 



The use of farmyard mariure. As a fertiliser farmyard 

 manure is well supplied with nitrogen and potash, but 

 deficient in phosphates, and the best results are obtained 

 when the necessary artificial manures are applied some- 

 where in the rotation. The dung is usually put on to the 

 roots, especially to the mangolds and potatoes, some 

 also can go on the young seeds and some to the meadow 

 land. The time of application depends on the climate, 

 the crop, and the labour available. So far as labour is 

 concerned it is an advantage to apply the manure in 

 autumn or winter and get it worked in ready for the 

 spring, and this can be done in districts with an annual 

 rainfall of 30 inches or less. In wetter districts, however, 

 with a rainfall of 35 inches or more, better results have 

 been obtained by spring dressings. Cases have arisen 

 where autumn dressings on seeds mixtures have kept 

 the land so wet that young clover plants have suffered. 

 Berry has shown in the west of Scotland that spring 

 dressings gave increases of 50 to 60 per cent, in the 

 potato and turnip crops while autumn dressings only 

 gave 25 per cent, increase over the control plots ^. 



Farmyard manure sometimes contains many weed 

 seeds and the old practice was to kill them by throwing 

 the heap up loosely and allowing it to become hot. But 

 the modern threshing machine is considerably more 

 efficient than the older form, and the weed seeds are 

 more completely removed with the cavings; so long as 



^ West of Scotland Agricultural Bulletin, No. 65, 1914. 



