60 MASS. EXPERIMENT STATION BULLETIN 353 



Rose Chafer 



Macroductylus subsplnosus Fab. 



This insect is distributed from Canada and Maine south to Virginia and Tennes- 

 see and west to Oklahoma and Colorado. It is reported to be most destructive 

 in southern New England and the Middle Atlantic States. The beetles are most 

 abundant in and adjacent to light, sandy soil which they prefer for breeding pur- 

 poses. 



The beetles appear suddenly in great numbers when many early summer plants 

 are coming into blossom. They feed on opening buds, a single beetle being capa- 

 ble of destroying several. They later feed on flowers and fruit, often causing 

 serious damage. They also attack the foliage of many trees, shrubs, and vines. 

 Roses, grapes, and peonies are usually the most severely injured, but many kinds 

 of plants may be attacked when the beetles are abundant. 



The beetles are also dangerous to chickens. There are records of one-week-old 

 chicks having been killed by eating 15 to 20 rose chafers. 



Description. The beetle is about }/2 inch long and colored j^ellowish-brown 

 but may become darker. It has long, reddish-brown legs which are darker at the 

 lower end. The wing covers do not quite cover the tip of the abdomen. 



The eggs are oval in shape, white and shin\' in appearance, and about 1/20 

 inch in length. 



The mature larva, or grub, resembles the white grub of the June beetle but is 

 much smaller. The head is yellowish-brown, and the body white except the 

 posterior portion which is darker. The legs are dark. 



The pupa is light yellowish-brown and about 3/5 inch long. The last cast- 

 skin of the grub often clings to the posterior end. 



Life History. In June, about the time grapes come into blossom, the beetles 

 appear in great numbers and attack the buds and blossoms. The foliage of various 

 trees, shrubs, and vines is also attacked. The beetles usually feed for about 4 

 weeks but may be seen for about 6 weeks. Soon after emerging, the beetles mate. 

 The females then work their way into the ground a few inches and lay eggs. 

 Mating and egg laying occur almost continuously for a few weeks, a female 

 depositing from 24 to 36 eggs. Light, sandy soil is generally preferred for egg lay- 

 ing; pastures and areas devoted to forage crops such as grass, rye, corn, and 

 other grasses are often selected for the purpose. The eggs soon hatch and the 

 young larvae, or grubs, feed upon the succulent roots of grass and other plants, 

 becoming full grown by late autumn at which time they descend deep into the 

 ground below the frost line. The next spring they work up toward the surface 

 and transform to pupae in earthen cells. In a few weeks they become adults and 

 dig their way out to the surface where they proceed to attack the aerial parts of 

 plants. 



Control. No satisfactory method of controlling the rose chafer has yet been 

 found. A thorough application of 8 pounds of lead arsenate and 2 gallons of 

 molasses to 100 gallons of water has proved fairly satisfactory when the beetles 

 begin to appear. A second application may be necessary. 



Rotenone sprays, mixed according to the manufacturers' directions and ap- 

 plied as soon as the beetles appear, have given promising results in some cases. 



Small ornamental plants may be protected by screening during the active season 

 of the beetles. 



Hand-picking the beetles and immediately destroying them ma\- be of some 

 value for certain small plants. 



Soil which has been infested should be plowed and disked when the insect is in 

 the pupal stage and easily killed, which is about late May. 



