206 ANNUAL REPORT. 



they were all more or less affected, and on the south side of the 

 trees the bark cracked and peeled off. Some of the Transcend- 

 ents blistered and cracked their bark, and yet, in that condition, 

 formed a new bark over that and grew all right. The most of 

 them I cut down to the ground the next spring. I believed at 

 that time that all of the damage was done between the first 

 of December and the first of April. When I examined them 

 the first of December they appeared to be all right, and I noticed 

 this trouble along about the first of February; but noticed it 

 more, particularly about the first of April. The Eed Astrachan, 

 which was buried in the snow, started out without any bark 

 blistering at all. 



Mr. Pearce. I would like to ask the opinion of the professor 

 about this phenomena of the sap and the cells of the trees. 



Prof. Henry. It would take too long to go into that at this 

 time. 



Gen. Le Due. I would ask if, in using the arsenic to destroy 

 the colding moth, the eggs are not deposited too deep to 

 kill the insects in that way? 



Prof. Henry. No, sir; it is on the surface. By spraying the 

 tree it will catch them. The arsenic preparation is fatal when 

 eaten. It kills the worm and in some instances will kill the eggs 

 also. But, recollect that if you use the arsenic preparation you 

 must use it before the little worm has got into the apple, for 

 when he has gotten inside the little apple he is safe, and he 

 laughs at you. You must catch him after the egg has been laid 

 and about the time the petals fall from the blossoms. 



Gen. Le Due. The simplest thing is the vinegar. 



Mr. Underwood. This has been to me the most interesting 

 and profitable discussion of the session thus far. I hope we 

 may get a paper from Prof. Henry elucidating these matters 

 more fully than he has been able to do here to-night and trust 

 we may not be disappointed. I want to say in regard to the 

 injury to that oak tree from the bark bursting that I cannot get 

 it out of my mind, that it is not the freezing, but the sudden 

 thawing that does the damage. As the Irishman said, "It didn't 

 hurt him at all to fall off the house; it was the stopping." So I 

 think that when the sun comes out and warms up the south side 

 of the tree that that is the time when the injury is done. Of 

 course I am dealing with these things in a practical way, not in 

 a scientific way at least; and it is very pleasant to have some- 

 one who has given these things more thought and who is able to 



