58 THE SOFT SCALE OF THE PLUM. 



Owing to the enormous number of eggs laid by this species, 

 the rapidity of its growth, and the avidity with which it feeds 

 upon a large variety of trees and shrubs, it is to be regarded 

 as a dangerous pest. 



We kept careful watch during spring to determine the 

 date of the first hatching of the young scale, in order to know 

 when best to apply sprays fatal to it at this tender, unprotected 

 stage. The hatching proved to be late, June 12th still finding 

 no change, and it was not until late in June and early in 

 July that the young emerging from the eggs, were 

 observed crawling over the branches. They were found then 

 to be arranging themselves along the veins on the under side 

 of the leaves. By July 9th, practically all the eggs had 

 hatched. During this month (July), two tiny parasities were 

 reared from these scales, one Coccophagus Iccanii, Fitch (iden- 

 tified by Howard), a well known hymenopterous enemy of this 

 scale; another hymenopter, Blastothrix longipcnnis, Howard, 

 both belonging to the family Chakididac. We have also found 

 a Coccinellid, Hypcvaspis, sp., feeding voraciously upon what 

 appears to be this scale on the Jack Pine. In fact a few years 

 ago we found this Coccinellid so abundant amongst the Lecan- 

 ium scales on Jack Pine on the station grounds that we stopped 

 spraying and left the beetle and the scale to fight it out by them- 

 selves. The former, either entirely by its own efforts, or 

 aided possibly by the presence of parasites, came out vic- 

 torious, and at the present time there is little, if any, of this 

 scale upon our evergreens. 



Treatment: Pruning in the winter and early spring while 

 the scales are dormant, and destroying the infested cuttings 

 would seem to be practicable and desirable. They can also 

 be easily brushed off the limbs. Accessory to this, two or 

 three sprayings about July ist (or as soon as the young 

 scales are observed to be hatching), with a solution made 

 by dissolving a 5-cent cake of Ivory soap in five gallons 

 of water, is recommended. We suggest tliis as the result 

 of experiments made by this division of the Experiment 

 Station, in which tlic above solution gave good results. A 

 kerosene emulsion (i part stock to 15 of water), carefully 

 made and applied as a spray in the early summer, while 

 the voung are still active, is also recommended. To secure 

 good results kerosene emulsion must be made exactly 



