106 Nebraska Agricultural Exp. Station, Research Bui. 12 
DESCRIPTION OF PLATE XIX 
A. Cankers resulting from pure culture inoculations on stubs. 
B. Canker resulting from pure culture inoculation in xylem. 
C. Cankers resulting from ascospore inoculation on stubs. 
D. Canker resulting from ascospore inoculation in heartwood. 
