New York Agricultural Experiment Station. 253 



rounded by healthy rolls of callus. But on counting the annual 

 growths in section it became evident that the injuries resulting in the 

 exposure of patches of dead wood on normal looking trees occurred 

 at the same time as those on the dying trees. The difference in the 

 condition of the trees seemed therefore chiefly a matter of difference 

 in the degree or extent of the initial injury. 



In the orchards studied in 1909 no affected trees were found which 

 had been injured just preceding that vegetative season; in most 

 cases the initial injury had occurred two or more winters earUer. 

 The assumption that crown-rot is primarily due to winter-injury 

 had therefore not been deduced from observations on recent injuries 

 but rather from the fact that the initial injuries had all occurred 

 between the vegetative seasons, and could not on that account be due 

 to mechanical injuries arising during cultivation or to other agents 

 operating in the growing season; and also on the wide expanse and 

 often general distribution between two particular seasons' growth, 

 of a discoloration which frequently shows as a complete circle in 

 cross-sections made even at some distance from visible external in- 

 juries of a tree trunk. It was during the summer of 1910 while 

 studying a crown-rotted orchard near Coxsackie, N. Y., which had 

 been briefly reported on before, that some early stages of the disease 

 were observed. After examining the bark on the trunks of many 

 normal looking trees, two of the Baldwin variety, which had been 

 set nine years, were found to have complete girdles of dead bark 

 extending downward about 8 to 14 cm. from the surface of the 

 ground, and including the bases of the lateral roots. The wood 

 appeared normal except for the discoloration of the outermost 1 to 

 3 mm. of the alburnum. Most of the dead bark was loose and slightly 

 decayed, and the usual discolored zone just under the spring's growth 

 extended some distance above any external indication of injury. 



observations during 1910. 



The main object of the work in 1910 was to find all possible varia- 

 tions in the characters of the disease as it occurs in this State, and 

 at the same time make special note of the environmental conditions, 

 such as type and topography of soil, wind exposure and cultural 

 history of affected orchards. In most cases the varieties and the 

 relative degree they were affected were also recorded. The observa- 

 tions were made during late summer and fall. 



Several orchards were studied around Geneva, Junius, Clyde, and 

 along the west shore of Seneca lake; in and around Rochester, Cold- 

 water, Sodus and Oswego ; between Seneca and Cayuga lakes, around 

 Branchport on Keuka lake, and about Highland, Milton and Cox- 

 sackie in the lower Hudson River valley. Most of the orchards were 

 located by visiting fruit growers who wrote to the Station for infor- 

 mation regarding their diseased trees. 



