28 Director's Repobt of thk 



is recommended as a method of control, especially to save the young 

 foliage of the grape in the spring. 



When hibernating adults are on the young foliage, delaying 

 the removal of the young shoots at the base of the vine will tend 

 to keep the insects on the lower leaves and thus afford some pro- 

 tection to the more permanent foliage. The lower shoots should 

 be removed just previous to spraying. 



The false tarnished plant-bug as a pear pest. — In Bulletin No. 368 

 attention is called to an investigation which was undertaken to 

 determine the nature and habits of the causal agent in the pro- 

 duction of a diseased condition of pears, characterized by the cracking 

 open of the skin in small spots and the formation of protruding 

 granular areas. The studies conducted to this end have demon- 

 strated that the injuries 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. 



As is common with insects of this class, this species proves to 

 have 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 

 during the period coincidental with the conclusion of pollination 

 and the formation of the fruit. 



Experiments conducted by the Station during the past three 

 years have demonstrated that spraying as blossoms drop largely 

 prevents the formation 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. Thorough applications, 

 using liberal quantities of the spray, are essential to accomplish 

 the desired purpose. 



