INSECTS AFFECTING PARK AND WOODLAND TREES 55 



the following- |une in order to prevent the maturing of any insects they 

 may contain. It may be possible to prevent oviposition if the trunks of 

 shade trees are treated early in June with the carbolic soap wash described 

 on another page. This is simply a deterrent and is employed to render the 

 trunks so distasteful that the insects will not attempt to deposit eggs therein. 

 The most successful method of checking this insect, in case of valued trees, 

 is by careful eNaminations each fall and spring for characteristic signs of 

 borings. These are familiarly known as sawdust, and small comminuted 

 particles of wood or bark at the base of the tree or in bark crevices should 

 lead to a careful examination for their source. It will usually be found in a 

 burrow near the base of the limbs or in the adjacent trunk, and wherever 

 such injury occurs the borers should be carefully dug out, even though it 

 means much cutting, because the borers make extensive drafts on the sap 

 of the tree, on which they appear to live to a considerable extent. The 

 galleries are usually under perfectly smooth, apparently healthy bark and 

 within I4 to >< an inch of the surface. They should be followed carefully, 

 and if a wire is used it may be possible to trace the gallery by cutting in 

 here and there without e.xposing its entire length, something of particular 

 importance when the boring has a transverse or oblique direction. It 

 should in any case be followed to its end and the offender destroyed. This 

 may seem like an extreme recommendation, but it should be remembered 

 that if the borer is not killed, the nefarious work will continue and much 

 more injury probably result than from the cutting, since in most instances 

 the bark immediately over the gallery soon dies and after a term of years 

 we have exposed wood and subsequent decay. The writer has seen a case 

 where extensive borings by this insect were carefully cut out and the grubs 

 killed. Several of the galleries had an oblique direction and it looked as 

 though the cutting would cause much injury to the tree, which was in a 

 sickly condition and the owner feared it was going to die. It is sufficient 

 to state that the tree began to recover immediately after the operation and 

 nearly three years later was the picture of health (though not so large as 

 uninjured associates) in spite of the severe scars left after exposing the gal- 



