FUNGOUS DISEASES AND SPRAYING 65 



PEAR 



Pear Scab and Sooty Spot. These diseases seriously injure 

 certain varieties of pears. Their appearance, effect, and 

 treatment are the same as in the case of the apple. 



Results of spraying with Bordeaux mixture for scab : 



Flemish Beauty. 



Pear Blight or Fire Blight. Leaves and twigs turn black 

 and die ; caused by bacteria ; sometimes a very serious disease. 



Treatment. Cut off and burn all diseased parts as soon as 

 discovered, taking care to cut well below the seat of the 

 disease. 



PLUM 



Black Knot. Swellings on the limbs and twigs in spring 

 followed by cracking open of bark ; exposed surface soon cov- 

 ered by dark green velvety growth, producing spores ; succeeded 

 by development of characteristic hard, rough, black knot in 

 which is produced another crop of spores, mature about mid- 

 winter. 



Treatment. We have found that spraying with Bordeaux 

 mixture reduced the number of the knots about 25 per cent. 

 The most effective remedy, however, is cutting out the swel- 

 lings and knots as soon as they are discovered. The trees 

 should be carefully examined in the spring and fall when not 

 in leaf. The removed knots should be burned. 



Brown Rot. Hotting of the fruit at or just before the time 

 of ripening, accompanied by the development of grayish pow- 

 dery tufts on the rotted areas. 



Treatment. This is a very serious disease, and one difficult 

 to prevent ; the damage may be lessened by spraying. The 



