Established Fruit Trees 



the tie should be cut, or the swelling bark will be 

 badly damaged. 



" BIG BUD " DISEASE OF BLACK CURRANTS. 



Normal healthy buds on black currants are conical 

 in shape, but when attacked by the currant gall 

 mite (Eriophyses ribis) the buds are somewhat 

 globular and more or less swollen. A diseased bud 

 may contain thousands of mites, but to the naked 

 eye they are almost invisible, appearing as a fine 

 white powder. The abnormal growth is caused by 

 the mites biting the tissue of the bud. They extract 

 the juices, and the buds attacked seldom produce 

 any fruit. 



In some districts fruit growers have given up the 

 cultivation of black currants on account of this 

 disease, but the high price obtained for this fruit 

 in recent years has encouraged others to plant 

 healthy stock and to take precautions to prevent 

 infection. Old bushes which are very badly 

 attacked should be dug up and burnt at once, but it 

 is worth while to adopt remedial measures in the 

 case of young stock which is not badly diseased. 

 Bushes which are underfed and wrongly pruned 

 always suffer badly from this pest. These facts 

 should be kept in mind. 



A few years ago the life-history of the mite was 

 practically unknown, and hand-picking the swollen 

 buds was thought to be the only possible method 

 of dealing with the pest. We now know that the 

 mites leave the buds and they may be found out- 

 side during spring and early summer. Following 

 this discovery many remedies were tried with vary- 

 ing success. Dusting the bushes with a mixture con- 



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