INCREASED CROP PRODUCTION 113 



area* The same principle has been applied by Mr. 

 Seeley 1 in our own country. The results are tanta- 

 lizingly sufficient to show that there is something in 

 the principle if only we could find the right appli- 

 cation. 



Tillering is also stimulated, as perhaps might be 

 expected, by mechanical injury to the plant, such as 

 rolling with a heavy roller or sending sheep over the 

 land in spring to eat some of the young shoots. Un- 

 fortunately we know very little about the process of 

 tillering, and cannot therefore suggest other or better 

 ways of controlling it. 



Turning now to root crops swedes, turnips, and 

 mangolds the swelling of the root is of considerable 

 importance, because unless the root goes on swelling 

 the translocation of sugar from the leaf apparently 

 does not continue long; small roots contain more dry 

 matter than large ones, but not a great deal more. 

 Swelling is promoted to an extraordinary degree 

 by dressings of phosphates; indeed, the chief use of 

 phosphate hitherto has been for this purpose. On 

 the Agdell field the swedes grown without phosphates 

 are no larger than radishes, yet the same plot will 

 carry quite good crops of barley and wheat. As soon 

 as phosphates are added the swedes swell up to their 

 normal size, and produce the usual amount of sugar 

 per acre. We know of nothing else that produces 

 the same effect. The formation of tubers on the potato 

 plant may be a related phenomenon, and is of equal 

 or greater importance. Phosphates cause more tubers 

 to form, and also- -perhaps therefore increase the 

 amount of starch stored up. 



There are two broad methods of attacking these 

 problems. One is to find by search varieties of crops 

 possessing the desired properties to a marked degree, 



1 Jo-urn. Farmers' Club, May, 1915. 

 ( 948 ) 9 



