PAPERS ON BIOLOGY AND AGRICULTURE 213 



and maple. Probably the honey locust should be consid- 

 ered as a desirable species but hackberry and elm grow 

 altogether too slowly and have no special merit. Ash 

 has an extremely low rate of growth and its encourage- 

 ment is justified only by the high market value of the 

 wood. The highest returns from artificial plantations 

 would probably be derived from cottonwood and syca- 

 more, but such a plantation requires a cleared field and 

 involves almost prohibitive initial investments except on 

 land which is subject to overflow and is not liable to be 

 for some years in an organized drainage project. 

 April 26, 1923. 



