Graves: New Bark Disease of White Pine 
87 
We take this opportunity, however, to warn owners of white 
pine plantations to be on the watch for this trouble. Since it is 
quite probable that it is of a parasitic nature, it is advisable to 
remove all diseased trees and burn them, or at least the parts of 
the stem that are affected with the disease, in order to prevent its 
further spread. 
Sheffield Scientific School of Yale University, 
New Haven, Conn. 
Explanation of Plate CXX 
Fig. i. Photograph showing open area caused by the death of trees from 
the bark disease in a plantation of Pinus Strobus at Maltby Lakes, near New 
Haven, Conn. At the left, a dying tree, with yellowing leaves, and those of the 
latest growth much shortened : two trees entirely dead in the foreground at 
the right. 
Fig. 2. Photograph of canker at base of stem of 7 year old Pinus Strobus. 
X 2/5. 
