ECOLOGICAL INVESTIGATIONS . 

 UPON THE GERMINATION AND EARLY 

 GROWTH OE FOREST TREES 



BY 



RICHARD H. BOERKER 



A THESIS 



Presented to the Faculty of 



the Graduate College in the University of Nebraska 



in Partial Fulfillment of Requirements 



for the Degree of Doctor of Philosophy 



Department of Botany 



LINCOLN, NEBRASKA 

 January i, 1916 



