186 



EXPERIMENTAL FARMS 



4-5 EDWARD VII., A. 1905 



Leaves. — As migiit have been expected from the already observed contiimed in- 

 crease in organic matter and ash, the percentages of all these elements increase. 



Weight for weight, the leaves are very much richer in potash than either the 

 collars or dressed roots, and the percentage of this element, it will lye noticed, makes 

 a very marked advance as the season progresses. 



The same tendency is to be observed in the case of the phosphoric acid and lime 

 and nitrogen. It is thus seen that the older leaves, compared weight for weight, eon- 

 tain much more soil-derived plant food than the younger. 



Collars or Crowns. — Here we find a slight increase in the percentages of phos- 

 phoric acid and lime, but a falling off in the potash. 



The percentage of nitrogen shows a notable increase in this part of the beet as 

 the plant grows. 



Roots. — As the season advances, the following changes are to be noted : Tho 

 phosphoric acid slightly increases; the potash shows a slight, but more apparent de- 

 crease; the nitrogen apparently increases, though the gain is a small one. 



A review of the foregoing data when calculated on the dry matter (water-free 

 material) reveals certain interesting facts: 



Fertilizing Constituents of Sugar Beets : Calculated on ^Yater-f^ee material. 



Dates of Collection. 



1st collection, .July 29 

 ■2n(l I, Sept. 



;iid I. Oct. 19 



bo 



o 



y. 



]09 



•77 

 •97 



Leaves. — Neglecting slight diffei'ences, the dry matter of the leaves remains fairly 

 constant throughout the season (July-October) in phosphoric acid and lime. 



In potash and nitrogen the percentages decrease perceptibly, more particularly 

 during August. During September there is but little change. It is evident, there- 

 fore, that the increase of these constituents before noted as appearing in the fresh 

 leaves, is due to the larger amount of dry matter contained in the leaves as the plant 

 reaches maturity, rather than to any enrichment of that dry matte?. This points 

 to the greater absorption of these constituents from the soil in the early stages of 

 growth than subsequently- 



Collars or Crowns. — The phosphoric acid and lime do not vary to any large degree, 

 but the percentage of potash falls away very considerably as the plant approaches 

 maturity. The nitrogen suffers slight change, but the direction of the change is not 

 well marked. 



Boots. — The most notable fact to be observed is the large decrease in potash con- 

 tent, as the season advances, evidently due in a large measure to relatively less potash 

 being absorbed in the later months of the season and the fact that it is particularly 

 during this latter period that the sugar is developed, thus, as it were, diluting the mineral 

 constituents in the root. The lime is reduced to about one-half, from July to October, 

 very probably the causes being those just stated. There are minor fluctuations of the 

 other constituents, but they are not sufficiently marked to allow of hard and fast de- 

 ductions being made as to the general trend in content of these elements in the dry 

 matter as tlie beet ripens. 



