New York Agricultural Experiment Station. 309 



INTRODUCTION. 



During some seasons pears in different orchards in New York are 

 much disfigured with rough and hard corky spots, and are, besides, 

 liable to be considerably deformed. From the character of the 

 injuries it has always been suspected that the miscreant was an 

 hemipteron but the species seems not to have been positively known. 

 In 1908 the work of the insect was so prevalent that it was decided 

 by this Station to be a problem worthy of investigation, and steps 

 were then taken to ascertain the identity of the offender and to 

 develop, on the basis of life-history studies, a satisfactory method of 

 control. This study has been continued each year, but progress in 

 the knowledge of the insect has been disappointingly slow because of 

 the elusive habits of the adult and its sensitiveness under confinement 

 for purposes of observation. However, in spite of these difficulties 

 the essential facts of its life history, especially those bearing on the 

 stages most vulnerable to treatment, have to a large degree been 

 obtained; and because of the interest in the work of the pest, which 

 proves to be a plant-bug (Lygus invitus Say), it seems best to pub- 

 lish the data we have secured. It is hoped at some future time to 

 supply some of the details of the late-summer habits of the adult 

 which have so far escaped our attention. 



ECONOMIC NOTES ON PEST. 



EARLY ACCOUNTS OF INJURIES TO PEARS. 



While this insect has doubtless caused losses of varying degrees 

 of importance for many years and its destructiveness has been noticed 

 by numerous growers, public attention seems to have been first 

 attracted to the plant-bug by the nursery firm of Ellwanger and 

 Barry 1 Rochester, N. Y. In 1884 they observed injured young 

 pears and some insects upon them. Specimens of both were sent to 

 the State Entomologist, Dr. J. A. Lintner, who made the following 

 report: "Some of the pears of about one-half inch in diameter show 

 as many as forty blotches from an eighth of an inch in diameter 

 downward. From the minute puncture originally made the juice 

 as it has escaped has become hardened and granulated and with its 

 increase in size has split the skin in different directions, often in a 



>Rept. Inj. Ins. N. Y. 3:110. 1885(1886). 



