128 TREES AND TREE-PLANTING. 
sparingly ali over the United States. It was first intro- 
duced into this country for the purpose of feeding the 
silk- worm, but it has never proved of practical value. 
At the time of the silk-worm craze in 1830 the white 
mulberry took a big boom, but has since gradually sunk 
down into utter insignificance. It may, however, at 
some future period, arise to eminence as food for the 
silk-trorm. 
