February, '16] GOODWIN: GRAPE BERRY WORM 95 



where it swells in size, very close to the berry. If the brood of moths 

 is large, eggs may be found on almost every berry. At Venice, 0., in 

 August 1915, as many as 62 eggs were found on a single bunch of 47 

 Catawba grape berries. One section of the vineyard averaged almost 

 an egg to every berry on the vines. A large series of bunches were 

 examined and the number of eggs and berries were counted. Sprayed 

 sections of the same vineyard averaged a little less than one small 

 worm to the bunch of grapes. In 1913, similar conditions were found 

 at East Cleveland, and eggs were very plentiful in a number of vine- 

 yards, especially on the Catawbas. Many eggs were found in 1915 

 which turned dark and failed to hatch. They were readily broken, 

 but did not seem to be parasitized, rather appearing to be infertile 

 or else attacked by disease. 



In the latter part of August and the first few days of September, 

 small larvse can be found in abundance, but I have been unable to find 

 any full grown or almost mature larvse at this time. These larvse 

 develop rapidly through the last week in August and the month of 

 September. As the berries begin to ripen, the juices within the wormy 

 berries ferment, and the berry worm larva seeks an adjoining berry, 

 webbing the berries together as it attacks them. The juice of the 

 abandoned berries ferments and evaporates so that a large part of those 

 in unsprayed vineyards are only empty shells by picking time. The 

 berries look all right from a distance of 10 or 12 feet, but close inspec- 

 tion reveals the fact that what ought to be grapes are nearly all mum- 

 mies with only the form of the grape berries. Each full grown worm 

 in early October averages from 4 to 9 berries which it has injured or 

 rendered worthless. 



Control Experiments 



A large series of experiments for the control of the grape berry worm 

 were performed by Prof. H. A. Gossard and J. S. Houser at Kelley's 

 Island in 1907. The author made the larger part of the final counts 

 and completed the season's experimental work. Various poisons and 

 stickers or spreaders with fungicides were used on plots large enough 

 to demonstrate their practical value. Paris green, arsenite of soda, 

 and arsenate of lead were used in combination with Bordeaux mixture; 

 iron sulfate mixture, with resin soap, laundry soap, and arsenate of 

 of lead was used alone. The poisons were used at varying rates and 

 with single and double treatments, using the fixed spars on the trac- 

 tion spraying machine. Spraying, directing the nozzles by hand, was 

 also tried and compared with machine spraying. The following 

 tables indicate the results of the various treatments. 



