2 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 51 



are useful for ornamental purposes but do not give abundant 

 shade. 



The size of the trees you want will depend largely on where 

 they are to be used. Trees that grow tall — such as American 



Fig. 1. — Trees planted close together will serve as a windbreak or 

 sound barrier. Evergreens are especially suitable and effective for these pur- 

 poses. 



Fig. 2. — The densely branched, Fig. 3. — The clump birch is used ex- 

 smoof h-leaved, globe elm is an orna- tensively for accent purposes in land- 

 mental tree of unusual appearance, scaping. 



