40 The Sugar-Beet in America 



able them to make the greater part of their growth during 

 the cooler part of the year. 



Sunlight. 



Sugar is made by the action of sunlight on the chloro- 

 phyll of the beet leaf ; hence the storage of a large amount 

 of sugar requires a great deal of light. In northern 

 latitudes where days are long, the beet is able to store 

 sugar faster than farther south where the summer days 

 are shorter. For this reason, the growing period of the 

 north does not need to be so long. 



Workers in the United States Department of Agricul- 

 ture 1 as a result of experiments were led to the conclusion 

 that the sugar-content of the beet is not dependent on 

 direct sunshine. Diffused sunlight from a cloudy sky 

 seemed to be practically as good as direct sunshine. Sun- 

 shine probably has a sanitary effect, however, since at- 

 tacks of diseases are much greater during damp, cloudy 

 weather than during periods when the sun is shining 

 brightly. The effect of sunlight is so closely related to 

 temperature and moisture that it is rather difficult to 

 discover just what its effects are. 



Moisture. 



Favorable soil moisture conditions are essential to suc- 

 cess in beet-raising. A crop costing less to produce may 

 be raised where it is too wet or too dry for maximum 

 yields without the results being serious, since little is 

 involved. With sugar-beets it would not pay to go to 



1 Wiley, H. W., U. S. Dept. of Agriculture, Bur. of Chem. Bui. 

 No. 96. 



