46 THE MONTHLY BULLETIN. 



FUNGOUS DISEASES OF PLANTS. 



Peach-leaf Curl. 



This disease curls the peach leaves which afterwards fall, often with 

 part of the fruit which has become infested. A new crop of leaves 

 will appear later but the damage has been done. Spray with lime 

 sulphur solution 4.5 degrees Baume, (1.030) specific gravity, just 

 before the buds open in the spring. 



Apple Scab. 



Diseased apples have the characteristic scabby patches on the surface 

 of the fruit. Bordeaux mixture 5/5/50, is used just as the buds are 

 opening and again after the petals fall. If necessary the same mixture 

 is used at later intervals. Some growers combine arsenate of lead for 

 the codling moth with this spray to save making two applications. 



Apple Mildew. 



Apple mildew dwarfs the tips of the new shoots and their leaves 

 covering them with the white mildewy growth of the fungus. The 

 resistance of varieties varies. It has been hard to control but some 

 growers have obtained good results by using a solution of iron sulphide.* 



Pear Scab. 



The scab of pear is similar to apple scab and appears as dark brown 

 spots on the young fruit, leaves and sometimes on the blossoms. The 

 percentage of moisture in the spring determines the amount of damage 

 wrought by this fungus. Use Bordeaux mixture 5/5/50 formula, apply- 

 ing as with apple scab.t 



Melon, Cucumber and Cantaloupe Wilt. 



Vines affected with the fungus wilt and die with a dry rot of the 

 stems and leaves. The fungus lives in the soil year after year infesting 

 new crops as they appear, unless rotation is practiced with crops which 

 are not susceptible to this disease. 



Potato Scab. 



The potato scab fungus causes a scabby appearance on the surface of 

 the tubers, consequently lowering their commercial value. The use of 

 clean seed and treating before placed in the soil by immersing about 

 one and a half hours in a solution consisting of one pound of formalin to 

 thirty gallons of water. On badly infested soil plant to other crops for 

 several years. 



*R. E. Smith and Elizabeth H. Smith, Bui. No. 218, Cal. Exp. Sta., p. 1088. 

 tR. E. Smith and Elizabeth H. Smith, Bui. No. 218, Cal. Exp. Sta., p. 1153. 



