THE PEAR 



77 



night later the flies emerge. These larvae are easily 

 destroyed by spraying with hellebore or the arsenites. 



In a number of the eastern states a small insect, 

 the Pear Psylla, has recently caused serious damage 

 by sucking the sap from the leaves. The insects pass 

 the winter as adults, and in early spring deposit eggs 

 on the bark, especially about the buds. About a fort- 

 night later they hatch into young — called nymphs — 

 which suck the sap from the petioles of the leaves and 

 stems of the young fruit. Recent experiments have 

 shown that the young nymphs may easily be destroyed 

 by spraying with kerosene emulsion. 



Pear Psylla 



Magnified. (After Slingerland) 



FUNGUS enemies 



The Pear Leaf-blight is the most destructive 

 fungous disease of the pear for which the spraying 

 machine may be successfully used. It occurs both on 

 the foliage and fruit; on the former causing small, 

 discolored spots, and on the latter producing a very 

 injurious cracking of the skin. It appears soon after 

 the leaves develop, in the shape of small dull-red spots 

 on the upper surface ; then the lower surface becomes 

 spotted, and the spots gradually change to a dark 



