THE FALSE TARNISHED PLANT-BUG AS A 



PEAR PEST.* 



P. J. PARROTT ant> H. E. HODGKISS. 



SUMMARY. 



During some seasons, pears in New York are affected by a diseased 

 condition characterized by the cracking open of the skin in small 

 spots and the formation of protruding granular areas. Fruits serious- 

 ly injured are usually much deformed and undersized. The nature 

 and habits of the causal agent appears to have been little understood 

 or not definitely known. 



Recent investigations by this Station have demonstrated that the 

 injuries to pears are largely caused by a true sucking plant-bug 

 (Lygus invitus Say). The damage is done by the nymphs, which 

 attack both pear fruit and foliage. Grape blossom clusters are 

 also subject to attack. The adult is similar in appearance to the 

 well-known tarnished plant-bug which thrives on a large variety of 

 plants. The similarity in appearance of the adults of these two 

 insects suggested as a common name, for the former species, false 

 tarnished plant-bug. 



The insect has five nymphal stages. The nymphs of the first two 

 instars are pale, fragile creatures which are very active and subsist 

 largely on the juices of the tender foliage. In the older stages they 

 are more sedentary and attack both leaves and fruits. The habit 

 of feeding in rather restricted areas is responsible for serious injuries 

 to young pears. The destructive activities of the insects occur dur- 

 ing the period coincidental with the conclusion of pollination and the 

 formation of the fruit. 



Tests during the past three years have demonstrated that spraying 

 as blossoms drop largely prevents the deformation of the young pears. 

 The spraying mixture that is recommended is three-fourths of a 

 pint of tobacco extract (40 per ct. nicotine) to one hundred gallons 

 of water to which are added three pounds of dissolved soap. Thor- 

 ough applications, using liberal quantities of the spray, are essential 

 to accomplish the desired purpose. 



* Reprint of Bulletin No. 368, November, 1913; for Popular Edition, see p. 771. 



[308] 



