210 INTERNATIONAL CONGRESS OF VITICULTURE 



THE ROSE CHAFER. 



(Macrodactylus subspinosus Fabricius.) 



By F. Z. HARTZELL, 

 Vineyard Laboratory, Fredonia, New York. 



Perhaps no fruit insect is better known to eastern fruit growers than 

 the rose chafer, or rose bug, which not only feeds on grapes and other fruits 

 but by its depredations is a source of annoyance to the growers of flowering 

 plants. Its common name has been applied on account of injury caused to 

 roses. The literature abounds with references to its destructive feeding 

 habits. In the Chautauqua and Erie grape belt (extending from Erie, Penn- 

 sylvania, to near Buffalo, New York) it is not common except in several 

 localities but in these local areas it has produced considerable monetary 

 loss. 



This paper will be confined chiefly to the investigations and observations 

 of the writer except where otherwise mentioned so all dates given refer to 

 the south shore of the Lake Erie Valley in which the above mentioned belt 

 is situated. For this reason the dates will not be the same as in other parts 

 of the insect's range but it is believed that the relation between the time of 

 flowering of the grape and the emergence of this beetle will be found to 

 hold, judging from the writings of others. 



Economic Importance. 



It is difficult to estimate the financial losses caused by this insect. Being 

 almost omnivorous, we must include injury to other fruits and losses to 

 commercial flowers as well as damage to grapes. It injures cherries and 

 grapes to a greater extent than other plants, but occasionally causes serious 

 losses to apples. Nor are its ravages confined to these fruits since much 

 loss has been recorded on raspberries, blackberries, strawberries and florists' 

 plants. The beetles attacking the blossoms can do an immense amount of 

 damage in a short time but it is chiefly owing to its great numbers that it 

 works such havoc. 



History. 



The rose chafer was described by Fabriciusi who gave it the scientific 

 name Melolontha subspinosus. Latreille established the genus Macrodactylus 

 (which means great toe) and placed the species in this genus thus giving the 

 insect the present scientific name. The first account of its economic im- 

 portance was by J. Lowell (1826). 2 The following year Harriss published a 

 partial account of the life history of the insect. This author gave the first 

 complete account of the life history (1841). 4 The writings of other writers 

 occurs in the 1852 and 1862 Eds.) 



1 Fabricius, Syst. Ent. 1798. 



2 Lowell, J., Mass. Agr. Repos. and Jour. 9:143-147. 1826. 



3 Harris, T. W., Mass. Agr. Repos. and Jour. 10:1-12. 1827. 



4 Harris, T. W., Insects Injurious to Vegetation. 1841. (The same account 



