New York Agricultural Experiment Station. 301 



fence rows. The number of insects present was considerable. 

 Spraying with nicotine extract was done in the Feinen vineyard 

 on July 18-19 and in the O'Brian vineyard on July 22-23. At 

 this time many of the nymphs were in the fourth and fifth instars, 

 but the spray material was effective against them as was shown by 

 the difference in the conditions of the foliage and fruit in sprayed 

 and unsprayed areas. Table I. 



M. W. KINGSLEY VINEYARD. 



The leaf-hopper and the grape berry- 

 moth (Polychrosis viteana), were present 

 in this vineyard, at Ripley, so the problem 

 was more complicated than in the other 

 experiments, as an effort was made to 

 control both pests with the same spraying. 

 The application was planned for the third 

 week in July since the eggs of the moth 

 were present on the grape berries at 

 that time ; but the breaking of the sprayer 

 and unfavorable weather conditions de- 

 layed operations until July 27. The spraying was completed by 

 the 30th. This delay in the treatment gave opportunity for a 

 few of the hoppers to develop to adults but the majority of them 

 consisted of nymphs of the fourth and fifth instars. The material 

 used was arsenate of lead 6 lbs., " Black Leaf 40 " % pint, whale- 

 oil soap 3 lbs., water 100 gallons. The soap was used primarily 

 as a so-called " sticker " which might more correctly be called 

 a " spreader " for the arsenate of lead, but it is believed to have 

 added to the efficiency of the nicotine in killing the leaf-hoppers 

 for they were controlled very effectually notwithstanding the fact 

 that they consisted largely of the older nymphs. The eggs of the 

 grape berry-moth fortunately did not hatch before the spraying, 

 owing to the cool wet weather during the latter part of July, so 

 that the treatment proved effective also against the larva? of this 

 pest. 



Fig. 18.— Nymph op Grape 

 Leaf-Hopper. 

 (Fifth instar; enlarged.) 



