286 CULTUKE OF THE SUGAR BEET, 



The year 1 879 was a cold year and one of little light. The average temperature from 

 June to October, the duration of growth of the beet, was 59°. 5 at Paris, while the average 

 temperature is 16°.4 in a normal year. At Arras, where the summers are a little cooler 

 than at Paris, the average was 59° instead of 59°. 5. It should be noted that all 

 the late crops were very mediocre if not bad ; but in a crop grown upon a well 

 manured and deeply plowed field, and where all the plants were well chosen and 

 regularly separated, better results are attained than in ordinary culture. On the other 

 hand, for comparison it is necessary to take account of the error introduced in the 

 estimation of the quantity of the crop from results obtained with isolated samples, 

 whatever may have been the care observed in their choice. This remark is all the 

 more appropriate as the growth of the beet approaches completion, because the indi- 

 vidual qualities of each root are more marked. 



In 1879 the average weight of roots increased slowly at first, and until July 1 there 

 was a period of relatively good moisture, heat, and light, but the plant was still 

 slender and its organs of assimilation slightly developed. 



Up to the 20th of July rains became almost continual. The temperature and clear- 

 ness fell to a marked extent below their normal value for this season ; but the leaf 

 still developed very actively ; the root enlarged as well as could be desired, and the 

 percentage of sugar in the beet increased. This situation continued until July 30, 

 though there was considerable diminution of the rainfalls. From July 31 to August 

 19 the rains without disappearing became relatively rare. It was this part of the last 

 season during which the temperature and clearness more nearly approached the con- 

 ditions of an average year. The development of leaves suddenly stopped and even 

 became regressive ; but this was at the same time the period of most rapid increase of 

 the root and of the proportion of sugar it contained. It was about the time when the 

 percentage of sugar in the beet attained its maximum. 



If we compare the variations of weight of the roots with the quantity of water which 

 fell, we readily recognize that there exists a relation between these two data. The 

 variation of weight varies with the humidity of the soil without, however, being pro- 

 portionate to it. Temperature acts in the same way. The percentage of sugar in the 

 roots, like the weight of the leaves, increases rather in proportion to the degree of clear- 

 ness; the coincidence is not always exact, the increase in clearness slightly preceding 

 the increase in the proportion of sugar, and corresponding more closely with that 

 found in the leaves which elaborate the saccharine materials deposited in the roots. 

 It is not, therefore, from excess of water but from default of light and heat that the 

 years of rainy summer and autumn are poor years for beets. The consequence of this 

 is, that if in dry, hot, and light summers the fields can be irrigated in a suitable man- 

 ner, the best conditions for high yield will be realized. Irrigation is undoubtedly not 

 everywhere possible; but if growers were thoroughly convinced of its advantages it 

 would be adopted at points where it has not yet been practiced. 



There is another question quite as important, that of manures. The experimental 



field of M. Pagnoul was manured in the following proportions referred to the hectare,* 



making a strong manure. 



tKilograms. 



Barn-yard manure 20, 000 



Woolen waste 700 



Seed-cake 1,000 



Guano 300 



The beets were planted at the rate of 6 per superficial meter, t and the yield per 

 hectare was estimated as follows : 



Sugar, per cent, of beets 7. 94 



Weight of beets kilograms.. 63,000 



Weight of sugar do 5,002 



Weight of salts do 552 



Weight of nitrate do 145 



* Hectare =2.47 acres. t Kilogram = 2.2 pounds. {Meter = 39.37 inches. 



