-366 Forty- SIXTH Report on the State Museum 



does not attack perfectly healthy trees, and from the fact that it is 

 often found in trees affected with the " yellows," — years ago it was 

 commonly but erroneously believed to be the cause of the "yellows." 



As we are not acquainted with the entire life-history of this species, 

 II hope that you will be able to tell me from your observations whether 

 the beetles are at this time boring into the trees for oviposition or are 

 emerging from them. From the red dust that I find sprinkled on the 

 bark, I judge that they are entering, as the pear-tree Scolytus, 

 Xyleborus dispar, is known to do about the middle of May. If the 

 beetles are still resorting to the trees to commence their burrowing in, 

 a thick wash of sludge-oil soap and carbolic acid should repel them. If 

 very thoroughly applied, it might even reach and kill those that had 

 . already entered, if they have not penetrated too deeply. 



I wish that you would try the experiment of applying with an ato- 

 mizer to a single infested tree of not great value, undiluted kerosene, 

 ■ over the entire trunk, so as to have it enter the little holes that the 

 beetles have made. I do not think that kerosene thus applied would 

 kill or even injure the tree. I have atomized it freely over rose-bushes 

 and small branches of plum trees, without harm resulting. 



If this little beetle once takes possession of a tree — unless it should 

 be found that it can be effectually killed by kerosene as above sug- 

 gested — the fate of the tree is sealed and it can not long survive. It 

 had better be cut down at once and burned, rather than it should 

 remain as a breeding place for the multiplication of the pest. 



The wash that you name will be excellent for excluding the peach- 

 tree borer, and I do not know of a better one. 



I have noticed the P. Uminaris in my Western New York Horti- 

 cultural Paper of last year — "Late Experiences with Insects," — and in 

 my Fourth Report — in each quite briefly. 



Albany, May Sth, 1891. 



From the small piece of ^ bark received from Mr. Snow, there were 

 found on June 15th m the box in which it had been placed, four dead 

 and one living P. Uminaris beetles, with living ones still in the bark. 



To those who still entertain the belief that this beetle, in its attack 

 of peach trees is the cause of the "yellows," the reply made • by me, 

 through the Country Gentleman of November 3d, 1887, page 837, to 

 an inquiry from Ringwood, Ontario, Canada, may be of interest: 



Inclosed I beg to hand you specimens of an insect taken from one 

 of my peach trees. The inspectors for the yellows have recently been 

 through this district, and on examination, have condemned several 

 trees in my orchard and others. They say that the presence of this 

 iirisect is a sure indication of the yellows; also an examination of the 



