REPORT OF THE ENTOMOLOGIST. 



383 



ties were not uncommon at Brunswick in July and August the past 

 year. Of six grabs winch I cut out over half seemed unhealthy, per- 

 haps diseased by the water which had penetrated their mines. 



I have recommended protecting valuable shade trees by wrapping; 

 the trunks with bands of cloth well saturated with kerosene oil m 

 August and September, so as to drive off the beetles and to destroy 

 the freshly-hatched grabs, bat since discovering how easily the grubs 

 and castings of the freshly-hatched worms can be detected a few days 

 or weeks after the eggs have been laid, it seems obvious that the easiest 

 and surest preventive is to cut out the grubs when lying in their au- 

 tumn and winter quarters just under the surface of the bark. It is 

 almost impossible to destroy the fully-grown worms in their "mines" 

 or burrows, since the latter extend up the tree either directly under the 

 bark or are sunken in the wood. On one tree nearly destroyed by this 

 borer, out of about fourteen mines twelve extended upward. Hence 

 it is useless to try to find the hole and inject oil into it. There now 

 seems no reason why valuable shade maple trees should not be saved 

 by a few hours' close observation and removal of the young grubs, say 

 in September or Oetober. 



THE POPLAR-BORER. 



(Saperda calcarata Say.) 



This borer has been destructive to poplar trees on the shores of Casco 

 Bay, especially at the head of the bay west of Harpswell Neck, where 

 my attention was first called to its work by ex-Governor J. L. Chamberlain, 

 on whose estate at New Wharf a number of trees had died. The trees 

 in August are seen to show unmistakable signs of disease by the leaves 

 curling and withering. The presence of the larva within is easily de- 

 tected by the masses of castings resembling sawdust, which are thrown 

 out of the holes and falls down the trunk to the ground. 



Upon cutting down the trees and splitting them open, not only the 

 fully-grown larva, or grub, but also one or two pupae and several beetles 

 were found, the latter ready to issue from their holes. As many as eight 

 or ten larvae were found mining in a portion of a poplar trunk 10 inches 

 long and 5 inches in diameter. 



The wood was perforated in all directions, running under the bark 

 part of the way and sinking in various directions into the wood, some 

 of them extending side by.side along the heart of the tree. The longer 

 mines are about a foot in length, and about a centimeter, or four-tenths 

 of, and at times half, an inch in diameter. Part of the mine is more or 

 less stuffed with long, slender chips gnawed off by the larva. 



The worm and beetle have been already described and figured in 

 Bulletin 7 of the United States Entomological Commission, p. 118. 



INSECTS AFFECTING FALL WHEAT. 



By F. M. Webster, Special Agent. 

 THE AY HE AT- STRAW ISOSOMA 



(Isosoma tritici Riley.) 



On the 8th of May, in a field of fall wheat near Bloomington, 111., 

 which had produced a crop of the same cereal the previous season, I 

 captured two wingless females of this species, which were placed iu 

 alcohol. 



