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incisions in the epidermis of twigs and of leaves, and 

 tliroug thèse infection can take place. Really healthy 

 trees do not suffer so much from Tliri/ps. The oljvious 

 course is therefore to give the trees ail they require, and 

 to prevent everything which may affect growth adversely. 



A third cause is found in strong winds, which tear 

 the leaves from the trees or damage them; an efficient 

 protection of the trees to windward will diminish their 

 liability to the disease. 



In those cases in which it is noticed sufficiently oarly 

 that the branches hâve been attacked by the die-back 

 disease, the latter can be stopped by shortening the 

 branches down to the healthy wood. The trees then 

 form again strong new wood and often recover from the 

 disease. 



Lésions of the trees as a resuit of cutting back, but 

 also of unsuitable pruning or thinning, may affect the 

 tree adversely and sometimes even bring about its death, 

 if thèse opérations are not performed at the right time. 

 The numerous wounds, which are thus formed, give too 

 many opportunities to the fungus of the die-back disease 

 to infest the lésion and to enter the wood, especially in 

 the rainy season when the coating of the wounds with 

 tar cannot take place, or can only be done imperfectly. 

 Cutting back and pruning should always take place in 

 the dry season and for this reason it is distinctly ob- 

 jectionable in the rainy season. After the cutting off of 

 the branches, the surface of the wound should always 

 be tarred, so as to prevent the fungus obtaining a hold 

 on the branch. 



Since it has become évident, that Diploilla occurs fre- 

 quently on fruits which hâve died from other causes, or 

 on the skins of harvested pods, the removal of such 

 fruits and remains of fruits must be considered one of 



