292 Repokt of the Botanical Department of the 



Cytospora bursting through its periderm. The same fungus was 

 also fruiting on the dead portions of the branches and twigs. 



No additional bark had died at the basal end of the trunk of tree 

 5/6, and a thick callus had formed around the old wound. The tree 

 had a normal appearance and seemed to be growing nearly as well 

 as the untreated trees around it. 



The pits in the bark around the beetle holes were very small and 

 shallow. They had been delimited by cork layers and none were 

 found to reach the wood. 



Some additional observations in the Clyde orchards. — The orchards 

 which were discussed on pages 2G8-270 were visited again on June 18, 

 and August 7, 1912, and found in good growing condition. The 

 callus growths around the winter-injured places of the trees which 

 had had veneer protectors around the trunks had crowded the graft- 

 ing wax towards the center of the wound and appeared normal. 



In the other orchards the growth of callus around the injured 

 regions had also been considerable, as may be seen in figure C of 

 Plate XI. The roll of callus surrounding the wound is thick and 

 normal, and although the tree had been more than half girdled it 

 looks like its uninjured neighbors. As far as could be judged by 

 the removal of a small portion of the wax, no rot organisms had 

 entered the dead wood. It appears as though even such severe 

 wounds may be wholly covered on small trees in the course of three 

 years. 



The sprouts which had grown from stumps of completely girdled 

 trees were not as promising as it was thought they would be; it would 

 probably have been better to replace them by new trees 



A few trees in this orchard were injured during the wdnter of 

 1911-12, but on none of them was the bark cracked open. They 

 were more typically canker-like injuries. On the southwest side of 

 several of the Baldwin trees growth had been practically negligible 

 over certain irregular areas, usually of considerable length, while on 

 other parts of the trunk it had been considerable. The place of 

 transition from the normal to areas of negligible growth was dis- 

 tinctly marked by lines, as shown in figure B on Plate XI . The area 

 of no growth or the depressed region in this case, extended from near 

 the ground almost up to the first branches, and was broadest but 

 least marked at the crown of the tree. The " sunken " bark still 

 had a green color externally and contained much live tissue on June 18. 

 It was found to have some discoloration in the phloem region but 

 much more in the inner cortex. This tree had not been visibly 

 affected during the summer of 1911. On August 7 the entire outer 

 surface of the depressed region was brown and further gro\A^h had 

 made the fissure wider than it appeared in the above figure. By 

 removing the dead portions of bark it was found that the injury had 

 extended only to the phloem in most cases and that only here and 



