76 POPULAR FRUIT GROWING. 



vegetation. Potassium sulfide and other forms of sulfur 

 are used alone or in combination as fungicides. As noxious 

 diseases and insects are present on many plants at the same 

 time, it is a common and good practice to use an application 

 that shall combine the advantages of fungicide and insecticide. 

 A good illustration of this is Bordeaux mixture to which has 

 been added a small amount of Paris Green. Such a mixture is 

 an effective remedy for apple trees that are affected with scab 

 and the Codlin Moth. A very complete list of fungicides and 

 recipes for them will be found in the Appendix. 

 Diseases of the Apple. 



Apple Blight, Fire Blight (Bacillus amylovorus). This is 

 the disease that commonly kills the twigs and branches and 

 occasionally injures the trunks of apple, pear and quince trees. 

 Its cause is a bacterial disease which gains entrance to the 

 tree through wounds or through the flowers. The germs are 

 carried by insects to the flower. The insects are attracted by 

 the dark, mucilaginous fluid that oozes out of the diseased 

 wood in the spring and which is swimming with bacteria. 

 From the flowers and 'other centers of infection the disease 

 spreads through the whole plant. This is the disease which 

 so commonly kills the young growth of apples in June. 



Remedies. Some varieties are quite subject to it, while 

 others are only slightly, if at all, affected with it; hence it 

 may be avoided by selecting resistant sorts. When it ap- 

 pears the best treatment is to remove and burn the infected 

 parts, cutting considerably below where the disease appears. 

 The disease may be carried in pruning implements from a dis- 

 eased to a healthy tree. It may be well under some conditions 

 to disinfect pruning tools by the use of kerosene or in other 

 ways so as not to spread the disease by them. 



Bitter Rot (Olomerella rufomaculans) . The summer spore 

 stage of this fungus does serious injury to the apple in some 

 sections. It attacks apples before they are ripe and also ap- 

 ples in storage. The spots which appear become sunken, are 

 soft and have a bitter taste. On the surfaces of these spots 

 the spores issue in long, gelatinous, cylindrical masses. These 

 are washed apart by rain water and spread the infection. The 



