282 CULTURE OF THE SUGAR BEET. 



probably exact, that is to say, the injurious physiological action of nitrogen and of 

 potassium upon the production of sugar in the beet, is therefore confirmed. 



Nor would I omit to state that our test beets were of small size, and as the two- 

 series of experiments in the two years presented the same results and the same char- 

 acters, we may accept as exact the principle in question. 



The growth of the leaves gave place to a striking phenomenon. The beets manured 

 with nitrate of soda had more powerful leaves, indicating a large afflux of juice ; the 

 surface of the leaves was firm and brilliant. The beets manured with phosphate of 

 potash, on the other hand, bore leaves which were weaker, languishing and much more 

 sensible to the direct solar rays and to heat. 



According to the observations and results of vegetable physiology, it is a fact that 

 the production of reserve materials is accomplished in the leaves. The phenomenon 

 above mentioned, the rapid yellowing combined with a very prompt change of the 

 leaf, in consequence of which the reserves produced in them are more frequently given 

 up to the roots, was partly attributed to tbe higher content of sugar in the beets ma- 

 nured with phosphate of potash. The experiments of Deherain have confirmed this 

 opinion, that the sugar is produced in the leaf ; from this it follows that the richer 

 beets are those which have the most leaves. Besides, Sostmann has shown that the 

 content of inverted sugar in the juice of the root gradually diminishes, while the 

 stem of the leaves and the juice of the leaves themselves still contain it in important 

 quantities ; but the inverted sugar is in all cases an intermediate product of the trans- 

 formation of the starch of the granules of chlorophyle into sugar. 



An interesting observation has been made by Corenwinder: that the saccharine 

 content of the beet increases with the importance of the surface of the leaves. In our 

 studies the difference in the leaves of each series of experiments led us to make weekly 

 measurements of them. We recognized that the beets manured with nitrate of soda 

 showed, with regard to their leaf surface, a decided growth in length, while the other 

 roots, manured with phosphate of potash, showed in their leafy portions a develop- 

 ment in breadth. But the surface of the leaves may be compared with that of an 

 ellipse, and as in this surface, the increase of the shorter axis corresponds for the leaf 

 to an increase of breadth. The leaves manured with phosphate should have a greater 

 surface of leaves for the production of sugar. The manure of phosphate acts princi- 

 pally upon the development of the leaves of the beet, and in a manner more favorable 

 to the formation of sugar. 



In order to determine what role potash plays in this effect of phosphate of potash, we 

 last year made other experiments with this salt and with phosphate of soda. These 

 experiments showed that phosphoric acid combined with soda also acted favorably 

 upon the production of sugar, but not in as efficacious a manner as when combined with 

 potash. In the development of the leaves no striking differences were observed. In 

 these later days the question of Chili saltpeter has become (br id ante) one difficult to 

 treat. Our experiments in nutrition have not been favorable to this fertilizer. The 

 experments of Bodenbender have also given the same conclusions, especially with 

 regard to the purity of the juice. I would also mention an observation of Vilmorin, 

 which has its importance with regard to the prudence which should be observed in 

 the use of Chili saltpeter. Vilmorin found that nitrate of soda injured the gerinina- 

 tive faculty of beet seed. 



In the general reunion of the German Association of the past year, Professor 

 Maercker supported the use of Chili saltpeter for beets. ■ In the position in which the 

 orator was placed — he spoke especially of the immediate neigborhood of Magdebourg — 

 we could scarcely object to his conclusions. The principles of Maercker cannot be 

 generalized; he has himself elsewhere admitted this. As the experiments in manuring 

 at Eisleben have proven, such a generalization would soon be controverted by practice. 

 According to the tests in nutrition thus far worked out, and according to the prac- 

 tical experiments made up to this time, the use of Chili saltpeter as manure for the sugar 

 beet is, at least from the standpoint of the sugar manufacturer, to be prohibited. In some 



