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312 Report oF tHE BOTANICAL DEPARTMENT OF THE 
the winter of 1902-03, for its record shows that it had been 
marked in 1903 to be taken out. 
Cross-sections near the ground of a few of the older trees, 
taken out this autumn, may be seen from plates XVIII to XX. 
Several varieties are included. It is plainly evident from the 
blackened frost-line of some, that it was the youngest wood 
inside the cambium and not the cambium itself that was 
killed. As may be seen, wood-rotting fungi destroyed the 
woodcylinder inside the frost-line of some examples (plates 
XIX and XX), though others are unaffected (plate XVIII). 
Sporophores of a Pleurotus were found on the one having but 
three bridging regions of live alburnum and bark. In some in- 
stances frost-lines could not be seen in cross-sections four feet 
above the crown, while in others they were evident in sections 
of branches. It was difficult to determine the exact number of 
growth rings developed since the injury occurred, but it cer- 
tainly seems a safe estimate to say that it happened from 12 
to 14 years ago, and very probably the latter. The callus rolls 
are mostly normal, though they were evidently injured in some 
instances. A few of the upper roots of each of these trees 
were more or less rotted, yet fair crops of apples had been 
harvested from them in recent years. 
Crown-rot, like Bacillus blight, seems most prevalent in 
thrifty orchards. In two of the examples described, the winter- 
injury seems to have followed the first cultivation of sod or- 
chards, but there may have been other factors involved. 
However, there seems no doubt but that an unusually heavy 
succulent growth, which leads to late maturity of the young 
wood, is one of the main secondary factors concerned in the 
occurrence of both of these troubles. 
Portions of the crown, trunk and branches of a dying, 
Crown-rotted, Bottle Greening tree (which has been set nine 
vears) were sent W. P. Headden by F. C. Stewart. He re- 
ported, by letter, that arsenic is present in diminishing 
quantities from the crown upward. So it seems that, although 
