l'Ji;j.l PUBLIC DOCU.MEXT — No. 31. 33 



CHESTNUT BLIGHT. 



G. K. STONE. 



This disease, already referred to in our previous reports, lias 

 been with us now for live or six years, and in some sections has 

 become quite prevalent. It was first noticed in the vicinity of 

 Xew York in 1905 by Dr. W. A. Murrill, since which time it 

 has spread over considerable area. The writer has been ob- 

 serving the disease from the time it was first introduced, and 

 has been able to watch its increase in various parts of the 

 country. The fact that it has spread more rapidly and ex- 

 tensively southward than northward has led us to take an 

 optimistic view of the continuation of its ravages in Massa- 

 chusetts. 



Along with the blight has been a deterioration of the chest- 

 nut tree which does not seem to be in any way associated with 

 the l)light fungus. While no attempt has been made to survey 

 the State systematically, to learn the range of infection, our 

 examinations of diseased material sent in to the experiment sta- 

 tion the past few years have thrown considerable light on its 

 distribution. 



The first infections are naturally the worst, and are con- 

 fined in a general way to our river valleys, — the Connecticut, 

 Housatonic and Blackstone and their immediate neighborhoods, 

 while the eastern central section of the State still remains 

 comparatively free from the disease. 



The chestnut blight, like the elm-leaf beetle infection, ap- 

 pears to be working up through the Connecticut valley in par- 

 ticular, and this is the worst infected region in the State. To 

 one diseased tree found this year there will no doubt be seven 

 br eight next year, and this is the ratio of increase each year. 



The small, smooth bark trees are the ones most largely in- 

 fected, the old and rough bark trees being least susceptible. 



