CHESTNUT BARK DISEASE. 393 



shown in some of the peach orchards in the Hudson Valley. 

 * * * The dying of the trees (afterwards) at such unusual 

 and irregular times gave rise to much alarm among the fruit 

 growers in some localities. It was feared that a virulent attack 

 of the yellows had broken out, or some new and serious disease 

 had become prevalent." 



Whetzel, of the Cornell, N. Y., Station (Bull. 236, p. 133), 

 says concerning a supposed outbreak of the bacterial blight 

 of apple in that state: "Anything that reduces the general 

 vitality of the tree tends to render it more susceptible to attack 

 of the bacteria. I have already referred to the apparent effect 

 of low temperature in relation to this disease in the Hudson 

 River region. A long growing season during 1902, with exces- 

 sive rain, followed by a sudden and extreme fall of temperature 

 early in December, is referred to by growers in that section as 

 the beginning of the injury to their orchards. The winter that 

 followed was a severe one, with sudden and severe changes of 

 temperature during the early days of the spring of 1903. Many 

 trees failed to leaf out, and large cankers were now observed 

 on limbs and bodies of dead and dying trees. The general 

 conclusion at once prevailed that these dead spots were the 

 direct results of these weather conditions. * * * I am there- 

 fore of the opinion that many of the trees in the Hudson River 

 Valley and about Kirkville were cankered prior to the winter 

 of 1902-03. The severe weather no doubt weakened the trees 

 yet free from the disease, thus rendering them more susceptible 

 to attack during the summer of 1903. * * * The winter of 

 1903-04 was also a severe one, and no doubt added to the sum 

 of the injury already produced. To just what extent the 

 winter injury in this section is responsible for the death of the 

 trees is a question. In certain cases it was very evident that 

 the trees had died from this cause." This statement shows that 

 Whetzel recognized the importance of these winter injuries, 

 though apparently he made a mistake in considering blight the 

 major cause of the trouble. 



Stone, of the Massachusetts Station (Report 20, p. 123), also 

 says: "In previous reports attention has been called to some 

 of these troubles, more particularly to the extensive winter 

 killing which caused so much injury during the winter of 

 1903-04, at which time thousands of trees and shrubs were 



