vin.] TIME OF APPLICATION OF MANURES 267 



quantity of manure near the seedling in its early critical 

 stages is probably valuable, and as the roots of swedes 

 and turnips do not extend very deeply, the phosphoric 

 acid may be placed in the most likely place to reach 



them. 



But for more deeply rooting crops, hops and fruit 

 or even mangolds, it seems probable that superphos- 

 phate is often applied rather too late in the season, 

 and that if used as a winter instead of a spring dressing 

 it would have a better chance of getting well diffused 

 through the soil. Basic slag and other insoluble phos- 

 phates should be used in the winter or even the autumn : 

 there is no risk of loss, and as much rain as possible 

 is wanted to get them distributed in the soil. As 

 regards potash salts, Dyer's experiments go to show 

 that they descend further in the soil, and are a little 

 more subject to washing than the soluble phosphates : 

 for this reason, where sulphate of potash is employed, 

 as for potatoes, it will best be sown with the seed. 

 Where kainit is used, it is best employed as a winter 

 or autumn dressing ; there will be little loss of potash, 

 for this will get fixed chiefly in the surface soil. But 

 the chlorides, which are present in kainit and are 

 sometimes not wholly beneficial in their action upon the 

 crop, will be removed and washed out into the drains or 

 the subsoil water by the winter rains : the magnesia 

 salts also will be precipitated within the soil, and to a 

 large extent removed from possible action upon the 

 crop. Turning to the nitrogen compounds, it is 

 necessary to keep in mind that all of them will become 

 transformed into nitrates which are liable to be washed 

 out. All insoluble organic manures should be put 

 on before or during the winter : the decay processes 

 will begin, resulting in the formation of amino-acids, 

 ammonia, etc., which will become fixed in the soil, but 



