62 



The Ottawa Naturalist. 



[July 



the weight of clover material of the first season is greater 

 than that of the second year's growth, but, as the data 

 just recited show, this is not always the ca^e. Favourable 

 climatic influences have much to do with a productive luxuriant 

 growth of clover, and consequently as seasons differ so greatly it 

 is only to be expected that any rule as to yield would be subject 

 to many exceptions. The practical question as to the best time, 

 from a manurial standpoint, to turn under the clover, must, neces- 

 sarily, take many factors into consideration, and is capable of 

 several answers, according to conditions of soil and crop require- 

 ments. I may add, however, that the practice now generally in 

 vogue for some years past is one that receives support and com- 

 mendation alike from labratory and field results It consists of sow- 

 ing eight to ten pounds of clover seed with the grain crop of the 

 rotation ; if the crop of the succeeding year is to be Indian corn or 

 potatoes, the clover is allowed to remain until, say, the second or 

 third week in the May following (when there is usually a strong 

 growth, the plants reaching a height possibly of two feet) and then 

 ploughed under; if another crop of grain is to follow, the clover is 

 turned under at the close of the first season of growth, say in 

 October or November. 



It would be impossible to place before you in this address any 

 detailed account ot all our experiments — field and laboratory — and 

 I have, therefore, made the following estimate, based upon our 

 published results. The data may be interpteted as showing, 

 approximately, the manurial value of the clover crop : — 



Average Amounts, estimated per acre, of Nitrogen, Phosphoric 

 Acid and Potash, in Clover Crop, including roots to a depth 

 of nine inches. 



