412 Bulletin 266. 



influence of the spray which reaches such vines is clearly shown. The 

 seven check rows with fifty-four missing vines gave a greater total 

 yield than check plat V with only twelve missing vines. 



CONCLUSIONS 



The results of this experiment give additional evidence that the 

 Rot can be controlled commercially by thorough spraying with mix- 

 tures properly made and applied. It has not been demonstrated that 

 spraying will control the Rot in exceptionally wet seasons, but it will 

 practically eliminate the Rot in an average year. Consequently, the 

 writers strongly recommend that the grower make a special effort to 

 eliminate the disease every season. There will probably never come a 

 time when spraying will not be necessary, but by this eliminating 

 method the grower may be able materially to reduce the number of 

 applications. 



RECOMMENDATIONS. 



Plow as early as practicable, making a special effort to turn under 

 all rotten clusters and leaves. 



Keep all weeds and grass down. 



Instruct workmen to gather any mummies left on the arms and to 

 clean up the brush well. 



Do not allow basal sprouts to spread over the ground. 



Keep the vines off the ground. 



Spray thoroughly. The time of application will depend on the weather. 

 Contrary to common belief, the spray should be applied before rather 

 than after a rain. In general, the time of applications will be as follows: 



First, with Bordeaux mixture 5-5-50, at the time when the second 

 or third leaf is showing. 



Second, with the same mixture before the blossoms open. 



Third, with the same mixture soon after blossoms have fallen. 



About two more applications will be necessary and should be made 

 at intervals of ten days to two weeks. 



The spray should be applied at a pressure of at least 100 pounds. It is 

 better to use trailers for all the applications, but stationary nozzles 

 may be substituted for the first two sprayings. After the blossoms 

 fall the spray should be directed on the clusters and the tips of the 

 shoots. 



