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AGRILUS FOVEICOLLIS, MARS., AS A CAUSE OF THE DECAY 

 OF THE CULTURE OF ROSES IN BULGARIA. 



By Prof. S. A. Mokrzecki. 



Experimental Agricultural Institute, Sofia. 



During the months of May and June 1921 I investigated the cause of the serious 

 losses that had occurred among the i-ose-trees (especially Rosa damascena, Mill.) 

 which are extensively grown in Bulgaria for making attar of roses. The conclusion 

 arrived at is that the cause of the general decline in rose culture is inadequate 



Galls on stems of Rosa damascena, caused by the larvae of Agrilits fovcicollis, 

 Mars. — I, One-year-old shoot ; the bark is cut off and the burrows of the 

 three to four days' old larva may be seen ; no swelling is formed yet. 

 2, Two-year-old shoot, with a swelling near its base ; the top of the shoot 

 was beginning to dry up. 3, Two-year-old shoot, with the swelling cut 

 open ; several annular passages are clearly visible. 4, Three-year-old 

 .shoot, on which the swelling is very distinct ; by this time the majority 

 of the small branches had already faded. All photographs taken from 

 nature and slightly enlarged. 



