58 



THE REPORT OF THE 



No. 36 



to die. I began to despair of the situation until 1910, when I noted a considerable 

 improvement in the condition of the trees although the larvae vs^ere still disgust- 

 ingly abundant. 



This year (1911) I was delighted to find that they had practically disappeared. 

 Once more the tamaracks retained their beautiful soft foliage throughout the 

 season. 



Another saw-fly that has been troublesome of late, though in no way compar- 

 able to the Larch Sawfly, is Leconte's Saw-fly {Lophyrus lecontei, Fitch). (Fig. 25 

 is a closely related species.) I first noticed it in 1909 in a grove of young pines 

 about 10 to 18 years old, which have grown up in a part of the pasture that had 

 been fenced in for a few years, thus protecting the seedlings from the cattle a 

 sufficient length of time to give them a start in life. They were confined to a 

 very few trees growing near together, and although one or two very young trees 



Fig. 25.— Abbott's 

 abbottii). 



Saw-Fly (LiOphyrvs 



were nearly stripped very little other damage was done. In 1910 they appeared 

 again at the same spot hut in larger numbers, and affecting more trees. We re- 

 moved every larva we could find, but on another group of pines about one hun- 

 dred yards away, which had also been attacked, most of the larvae were out of 

 reach. As a result there were very few larvae found in 1911 in the first spot, but 

 on the other one several fairly large red pines were bady defoliated. They occur 

 on both species of pine, but seem to prefer the red. 



In 1909 I confined a number of the larvae but obtained only half a dozen 

 cocoons, which were spun among the pine needles, although the normal habit 

 is to spin underneath leaves and rubbish near the surface of the ground. Althougli 

 I did a good deal of searching for cocoons under the affected trees I found but 

 two, one of which had been parasitized. Nothing emerged from the bred cocoons, 

 probably because they had been kept too long indoors. 



The same grove of young pines in which Leconte's Saw-fly was first found has 

 also been abundantlly attacked by the White Pine Weevil {Pissodes strohi, Peck). 

 For the last three years I have removed all the infested shoots I could reach with a 

 long pruning hook, but no apparent good resulted as most of the work was done 

 in August, when a large percentage of the beetles had already escaped, and as no 

 provision was made for the liberation of parasites. This season they were rather 

 more abundant than usual, about one-third of all the trees in the grove bearing at 

 least one infested shoot and many having two or three. 



This insect particularly affects young bushy trees growing in the open, and 



