478 



BULLETIN 388 



to cover the base of the trees with the material, and also failed to apply it 

 sufficiently high on the trunk. As a result all the infestations, amounting 

 to nearly 1.3 per cent, occurred either at the base or above the highest 

 point of treatment. This is well shown in figures 126, 127, and 128. 



Another interesting point in connection with this block is in regard to 

 the check row. This row, running through the center of the block, con- 

 tained 639 trees. When the owner 'saw the excellent results in the treated 

 trees, he asked himself why he should not save most of the trees in the 



FlG. 128. TREE SEVERELY INJURED AT BASE, DUE 

 TO LACK OF TREATMENT THERE 



check row. Therefore on June 3, 4, or 5 he did not know the exact 

 date he treated 555 of these trees, leaving some at either end as a true 

 check. The treatment, even at this late date, had a marked effect, as 

 shown by the percentage of infestation found on June 23. During the 

 first week in June all the larvae were still at work in the cambium layer, 

 and wherever sufficient material was applied most of the larvae were 

 killed. The trees then readily outgrew the injury. The carbolineum had 

 no apparent effect in retarding growth. 



