baal. . 
ARIS Fete: 3S 8 AE) 
Pa AAP vies a 
SCIENTIFIC PAPERS. 
A DISEASE OF THE BLACK LOCUST (ROBINIA 
PSEUDACACIA, L.). 
BY HERMANN VON SCHRENK. 
The black locust, Robinia Pseudacacia, is a tree grown 
extensively in this country and in Europe, as an orna- 
mental tree, and in some sections for its wood, which ranks 
among the best known and valuable of the American tim- 
bers. It is a tree which has few enemies, but of the small 
number which do attack it several are very destructive. 
Of the insect enemies, the locust borer, Cyllene robiniae, 
Forster, is the most destructive.* It is responsible for the 
fact that the locust is not more universally grown for its 
wood, for it bores into the sound wood of living trees, com- 
pletely riddling it with holes which spoil the wood for 
lumber. 
The fungus diseases of the tocust are, as a rule, not very 
destructive. Aglaospora profusa De Not., Valsa cera- 
tophora Tul.f and several others are found on the twigs 
now and then. The wood of the trunk and branches is 
destroyed by Polyporus rimosus, Berk. This fungus grows 
on older trees in the eastern United States; it has been 
found from New York southward along the Alleghanies 
to Alabama and westward to Southeast Missouri. Dur- 
ing the last year it was found in great numbers on the 
* Jack, J. G. Notes on two troublesome borers. Garden & Forest. 
5: 426, 1892. 
Packard, A. S. Insects injurious to forest and shade trees. Bull. No. 
7, U. 8. Entomological Commission. 95. 1881. 
+ Sargent, C. S. Silva of North America. 3:38. 1892. 
(21) 
