586 



Journal of Agricultural Research voi. xvni. no. :i 



control row. The summarized data in Table VII will bring out the com- 

 parative behavior of the shaded and unshaded plants. >\ 



Table VII.— Effect of shading soybeans with cheesecloth, igi6 



The shaded plants show the typical effects of reduced light intensity 

 so often observed^ncreased elongation of stem, slender growth, en- 

 larged area of leaves, reduced production of dry matter. Besides these 

 effects the yield of seed was considerably reduced. For present pur- 

 poses the important fact is that although the maximum intensity of the 

 direct light reaching these plants was only about 43 per cent of the 

 normal, the date of blossoming was not affected in the slightest degree. 

 This is a striking contrast with the fact that by reducing the length of 

 the daily light exposure from an average of approximately 14 hours to 

 12 hours, or about 15 per cent, the length of the period from germina- 

 tion till blossoming was reduced from 51 to 21 days. It was observed, 

 however, that the seeds of the shaded plants were about a week later 

 than those of the control plants in reaching final maturity. 



In the 1917 tests the beans were planted June 27 and the shades 

 placed in position a few days after germination for the first series, while 

 in a second series the shades were set up at the time of blossoming. 

 Two grades of netting were used, the 6 by 6 and the 8 by 10 mesh. The 

 general behavior of the plants is shown in Table VIII. Here, again, it 

 is seen that reducing the intensity of fhe direct sunlight to maxima of 

 about 70 and 59 per cent, respectively, of the normal has shown no 

 effect on the date of flowering. 



Table VIII. — Effect of shading soybeans with 6 by 6 and 8 by 10 mesh cotton netting, igiy 



Treatment. 



6 by 6 netting from germination 



to maturity 



6 by 6 netting from blossoming to 



maturity 



8 by 10 netting from germination 



to maturity 



8 by 10 netting from blos.soming to 



maturity 



Not shaded 



Date of 

 blossom- 

 ing. 



Aug. 17 



Do. 



Do. 



Do. 

 Do. 



