DOTHICHIZA POPULEA IN THE UNITED 
STATES 
George G. Hedgcock and N. Rex Hunt 
(With Plates 194 and 195, Containing 6 Figures) 
A New Fungus Outbreak in the United States 
The black poplar {Populus nigra L.), especially the variety 
known as the Lombardy poplar, is one of our most beautiful 
ornamental trees. It is, however, subject to diseases which 
shorten its life. In the United States these diseases apparently 
have not been studied to any extent, as there is a lack of litera- 
ture on the subject. During the spring of 1916, many reports 
were received by the United States Department of Agriculture 
concerning a serious blight of newly transplanted black poplars. 
In one instance, every tree in a lot of thirty was killed back by 
cankers. In a second instance, nearly all of 630 trees were badly 
infected with cankers, and at least one fourth of them were killed 
back to tbe point of the infection. 
An examination of cankers from the trees mentioned above 
and from other localities showed that in a great majority of cases 
only one fungus was present in the cankers. This fungus has 
been isolated and studied. Morphologically it is identical with 
Dothichiza populea Sacc. & Briard. 
A number of nurseries in the eastern United States have been 
examined with reference to the presence of this disease. In 
some instances, varieties of the black poplar were found very 
much diseased, thus accounting for the specially bad outbreak 
among recently transplanted nursery stock. It was also ascer- 
tained that in a number of localities adjacent to the infected nur- 
series nearly all the black poplars and some of the Canada pop- 
lars, or cottonwoods {Populus deltoides Marsh), had been at- 
tacked by the disease. 
At the same time a hasty preliminary survey was made of sev- 
eral localities for the presence of the disease on poplars planted 
300 
