202 



Bulletin 236. 



8. Distribution and Severity of the Disease 



Since the first specimen of blight canker was 

 received from the Upper Hudson River region 

 early in the summer of 1904, evidence has been 

 constantly accumulating that points to a very 

 wide distribution of the disease. Numerous 

 trips during the last two seasons have con- 

 vinced me of its very general occurrence 

 throughout this State. Practically no orchard 

 of any size visited has been without some trace 

 of it. 



Certain sections have sufifered much more 

 severely than the rest of the State. The ac- 

 companying map (Fig. 82) shows the regions 

 known to be most seriously affected. No doubt 

 other localities have suffered as severely as 

 those indicated, but limited time and funds at 

 our disposal for this work have made a more 

 extensive survey impossible. A careful and 

 systematic examination of the orchards in all 

 of the apple-growing sections of the State is 

 very desirable, not only that the exact extent 

 and severity of this disease may be determined 

 but also that a comparative study of the dis- 

 tribution of other canker diseases may be made. 



As alrea :!y pointed out, the disease has been 

 epidemic only in a few ralh.cr well marked and 

 restricted sections of the State. In the Hudson 

 River valley north of Albany the canker has 

 destroyed nearly every young orchard. In the 

 region about Schuylerville and Saratoga its 

 ravages seem to have been most fatal. 

 Throughout that section a number of orchards 

 were set some ten to twelve years ago. These 

 were just coming into bearing when the dis- 

 ease began to appear in alarming severity. At 

 first only a few trees died here and there in 



Fig. 80. — Pruned stub can- 

 ker that had spread down 

 side of limb during early 

 spring of second year. 

 Diseased tissue cleaned 

 away, treated witli corro- 

 sive sublimate and 

 painted. Good calluses 

 formed. Canker ceased 

 to spread. 



an orchard, but by 1904 the loss had in many 

 cases reached more than 50 per cent, and a careful examination of sev- 

 eral orchards showed that not less than 95 per cent of the trees were 

 diseased. All along the line of the trolley north of Albany and about 

 Saratoga, the dead and leafless branches of the young apple trees bear 



