CHESTNUT BARK DISEASE. 397 



in itself, but was a culmination of a period of dry summers. 

 During this dry period blight has been most conspicuous in its 

 development and spread in Connecticut, culminating in 1911 

 with by far the most frequent complaints of damage and spread 

 to new localities. Its unusual prominence in 1911 was not con- 

 fined to Connecticut, for according to Rane (57, p. 49), Met- 

 calf wrote him: "During the past summer the disease has 

 spread more than in all its previous history." As we have 

 already stated, the winter and spring of 1912 were so wet that 

 much of the depleted moisture was restored to the soil. As the 

 result, the general aspect of fruit and forest trees, including 

 chestnut, showed great improvement over 1911, and along with 

 this came a more or less apparent let-up in the spread and 

 severity of the blight. 



The particular situation of the trees, according to our observa- 

 tions, often makes a big difference in the development of this 

 disease. Those on the edge of the forest, specially on the 

 southern exposure, have often showed the disease first and 

 most severely. Isolated clumps of sprouts in the open are very 

 susceptible. Forests that have been opened up by removal of 

 trees, especially if on hillsides with southern exposure, are where 

 we find the blight most prominent. Also we have sometimes 

 found it bad in the lowlands. All these represent conditions 

 where the trees suffer most from lack of moisture under con- 

 tinued severe drought. 



We have especially in mind a forest in Middlebury on a hill- 

 side with southern exposure where the blight became very 

 prevalent. There the trees unquestionably suffered severely 

 from lack of moisture due to the droughts and the opening up 

 of the forest by the removal of diseased trees. Many of 

 those left finally showed sun-scald cankers with accompanying 

 development of blight, at their base on the southern exposure, 

 while the protected northern sides did not. Young nursery 

 trees on this hillside also developed similar sun-scald cankers 

 the first summer they were set out. While this part of the 

 forest was being severely injured, trees on the northern exposure 

 showed very little of the blight. 



This observation agrees with the statement of Ashe (Tenn. 

 Geol. Surv., 10 B, p. n), who writes: "For many years the 

 chestnut on the lower mountains in the southeastern portion of 



