INJURIOUS AND BENEFICIAL INSECTS 11 



trees is punctured with many small, circular holes, made 

 by brownish black beetles less than i inch long. The inner por- 

 tions of the bark and sap wood are frequently filled with burrows. 

 The parent beetles enter the bark and make burrows, on either 

 side of which eggs are deposited, and the young work away from 

 the main burrow. There are probably two broods annually in 

 New York state. 



Treatment : burn badly infested trees. Apply carbolic soap wash 

 to trunks and limbs in early spring. 



12 Pear blight beetle (X y 1 e b o r u s d i s p a r). The bark of 

 affected trees is punctured with many small, circular holes made 

 by dark brown beetles about J inch long. Inner portions of the 

 bark and sap wood are filled with burrows. 



Treatment: burn badly infested trees. 



13 17 year cicada (Cicada septendeci m). Slit and 

 broken twigs with wilting 



leaves are characteristic of 

 the work of this insect, but 

 unless the trees are small not 

 much damage is done. Broods 

 appear at intervals of 17 

 years. The adult may be dis- 

 tinguished from the dog day 

 cicada by its bright red eyes . 

 and wing veins of the same ^ 



_ Fig. 11 17 year cicada 



color. 



Prevention: avoid setting out trees in last few years before 

 cicadas are due. 



14 Apple tree bark louse (Mytilaspis pomorum). Bark 

 infested with elongated brownish scales shaped somewhat like 

 oyster shells. The winter is passed as white eggs under old scales, 

 the young appear about June 1. A common scale insect which 

 sometimes occurs in large numbers, and infests many different 

 shrubs and trees. 



