20 a EXPERIMENT STATION. [Jan. 



DEPARTMENT OF BOTANY. 



A. VINCENT OSMUN. 



The work of the department during the last year has followed 

 along lines indicated in previous reports. Satisfactory progress 

 has been made on old and new projects, although war con- 

 ditions and the unusual weather of the last growing season, 

 which brought many calls into the field, interrupted and often 

 seriously interfered with orderly and consistent attention to 

 regular, projected research. War emergency projects of various 

 organizations and agencies received attention from members 

 of the staff. In general, the benefits from work of this sort 

 have not appeared proportionate to the time and expense 

 involved. A large part of such activities are properly ex- 

 tension work, and should not be confused, as was often the 

 case, with the research functions of the experiment station. 

 Much of the so-called co-operative war emergency work be- 

 tween outside agencies and State men was too hurriedly and 

 loosely organized to be effective, and often it seemed ill-advised 

 from the start. In perspective it appears that proper use of 

 State forces would have been more effective and efficient in 

 accomplishing certain ends. However, the important work of 

 the department was kept to the fore, and the interference of 

 transient outside activities with regular projects was minimized 

 as much as possible. 



Investigations having as their object the control of lettuce 

 drop, a disease caused by Sclerotinia lihertiana, have been under 

 way for several years. Control measures have been tried out 

 in the department greenhouse and on a commercial scale in large 

 lettuce houses in Arlington. Eminently satisfactory results 

 have been obtained from repeated trials. In addition to green- 

 house work on this disease fundamental study of the causal 

 fungus has been conducted in the laboratory. A bulletin em- 



