224 Bulletin 253. 



and 7, which were well sprayed and cultivated, averaged only 8 per 

 cent. loss. 



Iron sulfate mixture gave a loss of 22 per cent or a saving of 8 per 

 cent over the check plat. One could detect very little difference be- 

 tween the plat sprayed with iron sulfate and the check plat. This mix- 

 tuic appears to be ineffective — in fact-, little better than nothing — in 

 controlling the rot. 



The results obtained by burning the dingers are quite marked. It 

 is a question, however, whether it pays on a commercial scale. The 

 work was done with a large torch, made by the Pearsall Manufacturing 

 Co., Texas. The principle of the torch is the same as that of a plumber's 

 torch, except larger. It required one gallon of gasoline to burn the 

 dingers from one row of fifty-three vines, and working only on one side 

 of the trellis. Undoubtedly most spores were destroyed, but a few 

 escaped. More satisfactory work could be done by using an ordinary 

 plumber's torch and burning on both sides of the trellis. The burning of 

 dingers is not recommended for commercial work. 



The effect of spraying and cultivation on the health of the vine and 

 maturity of the fruit was very marked. At the time of picking, the foli- 

 age on the experimental plat was green and healthy. Very little had 

 fallen from the vines, whereas the foliage on other parts of the vineyard 

 which were not well cultivated nor as thoroughly sprayed had mostly 

 fallen. The few that remained were yellow and ripe. Practically, it is 

 desirable to have an abundance of foliage in the fall. In case of frost, 

 "^he foliage acts as a protection. 



The fruit on the experimental plat ripened the earliest of any on the 

 vvhole vineyard of 150 acres. They were sweeter than elsewhere, and 

 could be picked first. As to the cause of this, the writer will not attempt 

 to make a positive statement. It is his opinion, however, that it was the 

 result of cultivation more than spraying. 



The result of work at Penn Van. 



A demonstration experiment to control the black rot was carried on 

 in the summer of 1907 in the Keuka Lake region. The work was done 

 in the vineyard of Mr. S. C. Williams. Four rows in solid block and each 

 forty rods longs, were sprayed with Bordeaux, 5-5-50. Two adjoining 

 rows in solid block were left unsprayed as checks. The plat was sprayed 

 as follows: 



May loth, June 9th, June 28th, July 13th, (Bordeaux, 5-5-50), Aug. 

 7th, (Ammoniacal copper carbonate, 5-3-50.) 



The rot was first discovered on the leaves June 28th. The spots 

 were about one-eighth of an inch in diameter, and dearly defined, though 



