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BITTER-ROT OF APPLES. 



(_Gleosjporium versicolor, B. & C.) 



I send you several apples affected with a disease similar to grape-rot. The varieties 

 most subject to the malady arc Willow Twig and Ben Davis. Any information as to 

 the cause of the rot will be thankfully received.— (L. D. Grovcr, Cuba, Mo.) 



Answer. The rot is due to the attacks of a minute parasitic fungus 

 closely related to that which causes the disease of the grape now com- 

 monly known as Authracnose. As stated by you, the apple disease, at 

 least in its earlier stages, resembles that of the grape, caused by the 

 black-rot fungus. The disease under consideration first manifests itself 

 in the form of small, more or less circular, brownish or blackish spots, 

 which rapidly enlarge and run together, thus affecting the entire apple 

 in a very short time. As the disease progresses the interior of the fruit 

 becomes brown and soft, and finally the whole shrivels and dries up. 



The effects just described are due to the development of the vegeta- 

 tive part of the fungus — known as the mycelium — within the fruit. We 

 have found the spores in abundance on old apples collected under the 

 trees during the last of February. The rot frequently develops after 

 the apples have been stored for the winter, and in such cases it spreads 

 rapidly, and causes great injury. 



The only course of treatment which a knowledge of the facts in the 

 case suggests is to bury or burn all diseased fruit as soon as the rot 

 begins to show itself. Great care should be taken not to store fruit 

 that shows the slightest indication of the disease, and during the winter 

 it should be carefully looked over every few weeks, and all the apples 

 showing rot specks removed, for the disease will spread in the bin from 

 the diseased to the healthy apples. If this is thoroughly clone seriou s 

 loss during the winter may be avoided. 



As far as we are aware no attempts have been made to apply preventive 

 remedies to the trees. As an experiment in this direction we would 

 suggest that next spring the trees be sprayed with a solution of sul- 

 phuret of potassium, one-half ounce of potassium to 1 gallon of water. 

 Make the first application when the fruit is about half grown, and if 

 possible use a force pump with a nozzle of fine aperture for applying 

 the liquid. Eepeat the applications every two or three weeks through- 

 out the summer and note the effect, if any. The disease here described 

 is widely distributed. During the past year specimens have been re- 

 ceived from Mississippi, Texas, New Jersey, Arkansas, Missouri, and 

 other States. From our own experience with the malady, together 

 with the testimony of others, we feel warranted in saying that it is an 

 enemy to be dreaded, and fought against with every available means. 



PEAR BLIGHT. 



I send you by to-day's mail some diseased pear cuttings of the Le Conte variety. 

 The trees from which the cuttings were taken I set four years ago, being one year old 

 at the time of setting. The trees are on well-drained sandy lands, which has been 

 well fertilized with stable manure, cotton-see. 1 meal, and phosphates mixed with a 



