204 Bulletin 132. 



Salt, lime, hyposulfite of soda, potassium sulfide, etc., have 

 been used unsuccessfully. 



Experiments conducted by the Division of Vegetable Pathology 

 at Washington indicate that shading the plants by means of 

 screens is most effective ; but this seems wholly impracticable. 



The most pronounced results thus far with fungicides are in 

 favor of the ammoniacal copper carbonate solution, although in 

 one region sulfur has seemed more successful. At the New 

 Jersey Experiment Station in 1891, Halsted found that the yield 

 of marketable celery from a row treated with the copper com- 

 pound was nearly double that of an untreated adjacent row ; and, 

 moreover, application of the fungicide was not made until the 

 celery was already badly blighted. At the Connecticut (New 

 Haven) Experiment Station, Sturgis recommends the use of dry 

 sulfur at the rate of 2 lbs. for 1,200 plants. 



It is necessary to add a few experiments made in Ithaca during 

 the past season, in the field where the early blight was first 

 observed. As before mentioned, most of this celery was in an 

 advanced stage of growth, and badly diseased ; but it was thought 

 that if the fungus could be checked until lifting time, much good 

 might result, and at least a practical demonstration of the use of 

 fungicides for celery would have been made for the Ithaca growers. 

 Sulfur at the rate of i lb. to i,oco plants and a standard solu- 

 tion* of ammoniacal copper carbonate were used. An application 

 of one of these fungicides was made to each of two plats of celery, 

 and a larger plat untreated reserved as check, the treatment being 

 given on July 28, an exceedingly hot day. The following week 

 there were alternate rains and scorching suns, and at the end of 

 this time the plants sprayed with copper carbonate appeared 

 slightly scalded. There was then hot, dry weather for a week or 

 more, and on August 15 there was marked improvement in the 

 rov^^s sprayed with the copper compound, — so much so that it might 

 be detected at some distance. The rows dusted with sulfur 

 showed some improvement, but less than the sprayed plat. On 



* A formula often used is as follows : 



Copper carbonate 8 ozs. 



Ammonia water (26°) 3 pints. 



Water 45 gals. 



