14 MASS. EXPERIMENT STATION BULLETIN 409 



PART II— NOTES ON OTHER PESTS OF GRAPES IN 

 MASSACHUSETTS 



By W. D. Whitcomb, Research Professor of Entomology, and E. F. Guba, 

 Research Professor of Botany 



Although grapes are not attacked by injurious insects and fungus diseases as 

 severely in Massachusetts as in some parts of the United States, there are sev- 

 eral destructive pests which damage the vines and fruit. The more important 

 phases of the life history, habits, and control of these pests are summarized and a 

 spray schedule for the control of grape pests throughout the season is included. 



INJURIOUS INSECTS 



Rose Chafer — Macrodactyliis suhspinosiis (Fab.) 



The rose chafer or "rose bug" is one of the most troublesome and destructive 

 pests of grapes in Massachusetts. The beetle, which is about 3^ inch long with 

 yellowish brown wing covers and black head, body, and thorax covered with 

 yellow hairs, is well known and recognized by its long legs and awkward move- 

 ments. It feeds on the blossoms of a large variety of plants especially rose and 

 peony but has a decided preference for the buds, blossoms, and newly formed 

 fruit of grapes. 



The eggs are laid in the sod of sandy soil and the grubs feed on grass roots 

 throughout the summer. Pupation takes place the following spring and the 

 beetles emerge and feed about the tim.e that the grapes are in bloom. . 



Hand-picking is the most common method of combating the rose chafer on 

 home grape^'ines but it is a very discouraging task because of the continuous 

 migration of the beetles and the results are often very disappointing. Spraying 

 with lead arsenate at the rate of 5 pounds in 100 gallons of water (4 level table- 

 spoonfuls in 1 gallon) kills many of the beetles and it is more effective if 2 gallons 

 o{ molasses (2 tablespoonfuls) is added to make the spray more palatable. It 

 should be applied just before the grapes blossom or when the beetles first appear. 

 Various commercial sprays containing rotenone, if used about twice as strong 

 as the usual recommended dilutions, kill those beetles that are thoroughly wet 

 but give little or no protection against beetles which appear 2 or 3 daj's after 

 spraying. 



Crape Berry Moth — Polychrosis viteana (Clemens) 



Although it is one of the most destructive insect pests of grape in many grape 

 growing areas, the grape berry moth is seldom destructive in Massachusetts 

 where the over-wintering larvae are killed by low winter temperatures. A few 

 individuals usually survive, however, and provide the source for a more serious 

 infestation in seasons when a warm dry summer follows a mild winter. 



The pale brown moth with mottled lighter markings and a wide purplish band 

 on the wings is only J^ inch from tip to tip of the expanded wings. 



The moths emerge from the winter cocoons in fallen grape leaves about the 

 time the grapes blossom, and lay eggs in the flower clusters. The larvae of the 

 first generation feed on the blossoms and young grapes and develop into a second 



