350 Bush-Fruits 



ANTHRACNOSE 



Pseudopeziza Ribis, Kleb. 



Although not so well known as the gooseberry mildew, this disease 

 is one which often causes serious damage to currants and goose- 

 berries by attacking the leaves and causing them to fall prematurely. 

 The disease is widely distributed in this and other countries and 

 probably occurs wherever these fruits are grown. Some varieties 

 are more susceptible than others. Gooseberries generally suffer 

 less than currants. The fungus first appears on the upper surface 

 of the older leaves, causing small, round, dark brown spots, about 

 one-twenty-fifth of an inch across. A small black spot is soon formed 

 in the center of each brown one, and the entire leaf turns yellow. 

 The leaf and flower-stalks, young canes and fruit are also attacked. 

 On the fruit it appears as small black specks, being especially no- 

 ticeable on the gooseberry. See Plate XV. 



The fungus is spread during summer by spores which develop in 

 a fruiting body that is formed within the tissues of the plant. When 

 mature these fruiting bodies break through the surface and push 

 out the summer spores in a sticky mass which readily dissolves in 

 water and is scattered by wind and rain. The spores need moisture 

 for germination and the disease spreads more rapidly in damp cloudy 

 weather. 



Control. Bordeaux mixture at the rate of 5-5-50, or lime-sulfur at 

 the rate of 1 to 40 or 50, has been found an effective remedy. The 

 first spraying should be given about the time the leaves appear, and 

 be repeated at intervals of ten to twenty days. Five or six sprayings 

 are generally needed, depending somewhat upon weather conditions. 

 The foliage must be kept well covered throughout the summer if 

 the treatment is to be thoroughly effective. The addition of lead 

 arsenate, at the rate of two pounds to fifty gallons of water, 

 at the first and second sprayings, will control currant worms 

 as well. 



Experiments made by Cornell University Experiment Station in- 

 dicate that dusting with finely-powdered sulfur, nine parts, and 

 powdered arsenate of lead one part, is also effective in controlling 



