PEARS, PEACHES, QUINCES, ETC. 159 



Insects Injurious to the Pear. 



There are but two insects generally seriously injurious 

 to the pear, the San Jose scale and the pear psylla. The 

 former of these pests are destroyed by spraying with 

 the lime and sulphur mixture which the reader will find 

 described in the bulletins of the state experiment sta- 

 tions. Its presence upon the trees is not noticeable 

 except upon close examination. The leaves when at- 

 tacked are small, weak, light in color, and leaves and 

 twigs are covered with minute circular specks. These 

 specks soon become very numerous and when they are 

 scraped off with the back of a knife-blade slight exuda- 

 tions of a yellowish substance are seen. If one finds an 

 unusual covering upon the twigs, leaves or fruit, he 

 should send specimens at once to the local experiment 

 station, and follow directions as to their destruction, for 

 it takes but a year or two for them to spread over whole 

 orchards and ruin the trees. 



The pear-tree psylla is a minute brown aphis-like in- 

 sect that flies about the trees in early spring and lays its 

 eggs on the leaves and tender twigs. From the eggs 

 comes a small flattened aphis that feeds on the juices 

 of the tender tissues. Each one of these insects feeds 

 in a little pool of juice that is sweetish to the taste, 

 and wasps, flies, and hornets appear in large numbers 

 either to feed upon the insects or upon this sweet liquid. 

 The presence of the aphis may be known by the large 

 number of these attendants. After the insects have 

 worked a while the leaves, twigs and fruit are covered 

 with dirt-like masses, where the dust of the atmosphere 

 has adhered to the sticky exudations of the insects. 

 This pest has not been controlled satisfactorily in the 

 past, but it is claimed that the lime and sulphur mixture 

 used for the San Jose scale will destroy these also. If 



