74 EXPERIIMENT STATION. [Jan. 



Trees gi'ow in jji'oportion to the amount of foliage they 

 develop, as well as to the amount of light they receive. Those 

 growing on the east side of mountains develop most on the east 

 side, and those on the west side will develop most on that side 

 of the trunk. We found 28 per cent, difference in favor of the 

 east radii of some stumps growing on the east side of a moun- 

 tain, and 8 per cent, difference between the east and west radii 

 of trees growing on the west side of mountains. The gTowth 

 of trees differs greatly according to the exposure ; as, for ex- 

 ample, on the edge of forests the growth is greater than in the 

 middle of the forest, proving that light affects growth mate- 

 rially. 



In the case of the trees on the east and west sides of 

 mountains, they will receive sunlight during only part of the 

 day, and their development will coincide with the amount of 

 light they receive, as well as depending also on the side of the 

 tree exposed. Since morning light is more intense than after- 

 noon light, the east side of a tree will show the greatest growth, 

 and a great mau}^ measurements of trees and of light intensity 

 at different times during the day have shown us that the 

 growth of the tree in one direction or another is directly in 

 proportion to the light they receive. 



In conclusion we might repeat that elms thrive better in 

 pastures where the grass is likely to be scant, than in mowings, 

 and lawn conditions are more or less favorable. They also 

 respond to cultivation and treatment with fertilizers like any 

 other crop. 



