1922 



ENTOMOLOGICAL SOCIETY. 



41 



Mortality Due to Location of Overwintering Eggs : In cases where the over- 

 wintering eggs were located a considerable distance from the leaves, for example, 

 near the crotch or on the trunk, it was observed that quite a number of the minutj, 

 newly-hatched larva? perished before reaching the leaves. 



Artificial. 



Lime Sulphur: It is very fortunate that, in order to successfully combat the 



spider mite on plum trees, it is not necessary to make any special applications or 



to use any special spray material. Our experiments have shown definitely that 



the pest can be controlled by spraying twice with commercial Lime Sulphur 1-40, 



Overwintering eggs on plum twig. X 10. 

 Plum Spider Mite; male and female. X. 10. (Inset) 



at the times recommended for the control of Brown Eot, Curculio, etc. viz: (I) 

 when the fruit is set and most of the calyces have dropped and (2) two weeks 

 later. Needless to say the spraying must be done very thoroughly. 



The results secured in a Vineland orchard in 1920 were very striking. . One 

 large block of plum trees was sprayed with Lime Sulphur and another adjoining 

 block, with the same varieties in it, was sprayed with Bordeaux mixture. By 

 midsummer the foliage on the trees sprayed with Bordeaux mixture was pallid, 

 largely functionless and stood out in very marked contrast to the healthy, green 

 foliage in the blocks sprayed with Lime Sulphur. 



