CONTROLLING DISEASES AND INSECTS 551 



dry are burned without being removed 

 destroys many insects and diseases. 

 Thorough cultivation is then practiced, 

 and the new canes make a solid row 

 for the next year's crop. 



11. Controlling Diseases and Insects. 

 The diseases and insects that trouble 

 the brambles are relatively few, but 

 some are very destructive. The grower 

 should be familiar with the more im- 

 portant ones. 



These are anthracnose, attacking 

 all brambles, but especially virulent 

 on the black raspberry; cane blight y 

 also severe on black raspberries, but 

 affecting all raspberries; crown gall, 

 infecting chiefly red and black rasp- 

 berries and blackberries; orange rust, 

 destructive to blackberries and dew- 

 berries and occasionally to black rasp- 

 berries; and double blossom, seriously 

 affecting blackberries and dewberries 

 in Southern sections. Follow the con- 

 trol program of the local experiment 

 station. 



The mosiacs and other virus dis- 

 eases are very destructive to rasp- 

 berries, especially red varieties in some 

 sections. In parts of New York the 

 industry has disappeared by reason of 

 the inroads of these diseases. No 

 parasitic organism has been discovered, 

 but juices from an infected plant, when 

 introduced into a healthy plant under 

 proper conditions, will result in infec- 

 tion. Thus the term ^'virus'' diseases. 



from the field. This 



{U. S. D. A.) 



Fig. 234. These shears 

 are in common use in 

 some sections for pruning 

 dewberries. The blades 

 curve upward so that the 

 operator may cut the 

 canes close to the crown 

 of the plant without 

 much bending over. 



