VEGETABLE DISEASES — ROUND TABLE • 199 



judgment. Spraying in every case is protective in nature, that is it 

 is a preventive and has no virtue whatever for curing plants that are 

 already infected. I should point out one thing always to be remem- 

 bered, namely, that the period intervening from the time of entrance 

 of the germ tube of the spore into the leaf until the time when you can 

 see the spot is a good many days, in some cases as long as three weeks. 



STORAGE ROT OF CELERY 



The rot of celery in storage has been an important problem the 

 past season. The disease is often referred to as pink rot on account 

 of a characteristic pinkish discoloration which appears at a certain 

 stage in the decay of the stalks. The disease most often starts at the 

 "leaf joints," especially where leaflets are broken, but may appear at 

 any slightly bruised place on the stalk. The affected leaves become 

 soft, turn pinkish, then brown, and finally are a slimy, decayed mass. 

 The fungus responsible for this trouble is a species of Sclerotinia, 

 probably S. lihertiana, a common rot producer. 



This past fall I was in a storage house on a Saturday when the 

 manager told me that a certain car of celery looked to him as if it was 

 going down. The next Saturday he called me on the telephone and 

 told me it was in bad shape and sent me a crate, which, when it 

 reached here, was in an advanced stage of decay- — all of the outer 

 leaves rotten. The same day that this car of celery was received at 

 storage, another one came from another source. The temperature 

 of the cars was taken and was found to be fifty-six in each case. The 

 two cars were unloaded and placed in the same room on the same day. 

 One went down just before Thanksgiving, the other was held for the 

 Christmas trade. The fact that the disease almost invariably starts 

 at the broken joints and that the fungus works more rapidly during 

 hot weather are points of great importance in control. Then, the 

 matter of precooling of cars seems to me to be of the greatest im- 

 portance of all. The cars are often delivered with ice. They are 

 cool to be sure; then they are filled with crates of hot celery packed 

 close together. It is known that, in the case of oranges, the cars that 

 are simply iced, then filled and started across the country, do not get 

 down to a temperature of forty -five until they have been five or six 

 days on the road. That being the case, I question very seriously 

 whether, in shipping celery which is to be on the road only twenty- 

 four or thirty-six hours, it is worth while to bother with the ice, — but 

 the question of precooling after the celery is actually in the car is a 



