6o AGRICUVrURE OF MAINE. 



larger than the stem mothers and usually lighter green in 

 color. This is the migratory form and furnishes the principal 

 means of distribution of the insect. In the fall the females, 

 instead of producing their own kind, give birth to true sexual 

 form, male and female. These mate, after which the new 

 females lay the eggs on the twigs. 



A great deal of work has been given to the best method of 

 controlling this pest, with more or less success. As a general 

 thing, the best spray mixture in use at the present time is black 

 leaf 40, combined with sufficient soap solution to render it 

 properly adhesive. It has been found that the time of day ha? 

 a great deal to do with the efficiency of the material. Cloudy 

 days, when the humidity is high, and late afternoons, are gen- 

 erally considered the best times for applying the material. This 

 is due, no doubt, to the relatively small amount of evaporation 

 gomg on at that time, as rapid evaporation has a tendency t 

 reduce the effectiveness of any contact spray. 



Tobacco stems, kerosene emulsion, whale oil soap and even 

 ivory soap, have produced good results when properly applied. 



THE SHOT HOLE BORER. 



Upon examination it is frequently observed that many of 

 our trees have been perforated with very small holes, not more 

 than a twentieth of an inch in diameter. This infestation is 

 more commonly observed on the less vigorous limbs of large 

 trees. However, neglected young trees are often in the same 

 condition. It is an indication of the presence or rather the 

 work of the shot hole borer, a minute beetle about a fifteenth 

 of an inch long. Many of the Gregory orchards this year were 

 infested with this beetle and are in a fair way to be killed un- 

 less something is done to prevent further depredations. Each 

 hole represents the exit hole of the beetle and leads to a short 

 channel usually running with the grain of the wood, from each 

 side df which burrows lead off at right angles which gradually 

 enlarge and terminate in a round cell. 



The grub of this beetle hatches from an egg which has been 

 deposited in the main burrow and the smaller channel is due to 

 his work. The increase in the size of the branched channel is 

 due to the increase in .the size of the grub which has been feed- 



