104 CULTURE OF THE SUGAR BEET. 



France. But while all admit the value of the judicious application of 

 the nitrates, it appears also to be the universal opinion that it should be 

 accompanied by the application of a corresponding quantity of the 

 phosphates, which have a tendency to counteract any prejudicial influ- 

 ence that the nitrates may exert by hastening the maturity of the plant 

 and increasing its sugar content. This fact has been very nicely elabor- 

 ated by Professor Maercker, of Halle, in a lecture lately delivered upon 

 the subject of beet culture, an abstract of which may be found in the 

 Journal dcs Fabricants de Sucre. He says it is a well-accepted fact that 

 strong doses of nitrogenous manures are injurious to the beet crop, in 

 that it increases the weight of the non-saccharine contents and reduces 

 the sugar. The discredit into which the use of nitrates has fallen is due 

 to its abuse and the manner of applying it. The difficulty appeared to 

 be to determine the quantity to use and the best time to apply it. When 

 applied too late it retards ripening. Applied in spring the plants de- 

 velop vigorously in leaves and root and the period of growth is length- 

 ened. So strongly nitrogenous manures always produce growth. 



But the sugar-beet must ripen to accumulate sugar within it. Its growth 

 should therefore be arrested to admit of ripening, which late distribution 

 of nitrates prevents. At Magdeburg part is applied in the fall and the 

 remainder before the preparation of the soil in spring. Heavy doses of 

 strongly nitrogenous manures also necessitate heavy doses of phosphoric 

 acid to annihilate the injurious effect of an excess of nitrogen. Phos- 

 phoric acid applied in large quantity induces early ripening of the plant. 

 A mellow, permeable, clay soil may receive doses that would be injurious 

 to a cold soil. 



Pagnoul has developed by his researches and observations that phos- 

 phoric acid gives varying results. In some soils no appreciable effect 

 can be noticed, while in others its use has been found very favorable, 

 and these differences are attributed to the greater or less proportion of 

 phosphoric acid already existing in the soil. Notes should therefore be 

 kept of the effects of various manures in order to avoid unnecessary 

 expense in their application. M. Decrombecque considers that in all 

 cases the phosphoric acid in the soil should be increased as the nitro- 

 genous principles increase, and Woussen considers phosphoric acid a 

 corrective for the deleterious influences of nitrates, because upon soils 

 where nitrate of soda has been applied in large doses it is only neces- 

 sary to increase the proportion of phosphates of lime to secure good 

 maturation of the crop, which would otherwise remain green. 



Pellet * has advanced some interesting notions concerning the com- 

 parative values of the different elements of plant-food in their rela- 

 tion to the production of sugar in the beet, deduced from the study of 

 analyses of different plants obtained by various persons in their exper- 

 iments. Lawes and Gilbert, discussing the analyses of wheats grown 



upon the Eothamstead farm, and of French wheats analyzed by Bous- 



. , . . — . 1 **. 



* Journal dea Fabricants de Sucre, October 2, 1878. 



