384 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 17 
In my little orchard, the past year, nearly all of the apple trees, about 
40 in number, were badly infested with the round-headed borer. After 
some desultory work, attempting to dig out the larvae with a knife, I 
began the use of carbon disulphid. The results were so satisfactory that 
I will describe the procedure in some detail. 
Slingerland and Crosby (Manual of Fruit Insects, page 192) say 
“Other kinds of borers in shade or park trees have been successfully 
treated by injecting a little carbon disulphid into the small hole from 
which the sawdust-like excrement is being pushed out, and the hole 
quickly plugged with putty or grafting wax. The deadly fumes of this 
very volatile liquid penetrate the burrow and finally kill the borers. 
Orchardists should give this sensible method a thorough trial. A 
similar treatment has been successfully used by some fruit-growers.” 
This method, while advantageous where the hole of the burrow is 
clear-cut, cannot well be applied in cases where there are a number of 
holes leading into communicating burrows, or where the holes are in 
part below the sod. Treatment by the method to be described was 
begun late in July, and continued, as more infested trees were discovered, 
until into September. 
The following recommendations, if carefully observed, will com¬ 
pletely control this apple-tree pest. 
1. Clear away water sprouts, grass, and sod from around the base of 
the tree for a distance of 6 inches. This is good orchard practice in any 
case. Rough bark and borer-frass should also be brushed away. As the 
holes in some cases are found below the surface it is well to scratch the 
soil away from the base of the tree to the depth of about an inch. 
2. After one or more days, the trees should be examined for indi¬ 
cations of renewed activity of the borers to be sure that time is not 
wasted on a tree from which the borers have already departed. In 
some cases, especially late in the season, some weeks may elapse before 
more frass is thrown out after the tree has been cleared at the base. 
3. Mix some fine, homogeneous clay with a little water, until it is 
perfectly smooth and has the consistency of putty or plasticine. Prob¬ 
ably any fine soil will answer provided it is free from stones and sticks, 
and not crumbly. If the clay is from the surface and very dry it will 
facilitate matters to let it stand for several hours with a little water 
poured over it. A pail full of this plastic material is enough for five to 
ten trees. With increased experience a smaller amount of clay may be 
used per tree than at first. 
4. Wet the soil at the base of the tree. If the soil is porous, work a 
