ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 73 



the bark and cambium and may girdle and kill a branch or an 

 entire plant. 



Control Measure 17 (end of circular). 



Taxus Mealybug, Dysmicoccus cuspidatae (Rau), fig. 51. — 

 The taxus mealybug is an occasional pest of yew. Its name is 

 descriptive of the white, waxy, slow-moving, sucking insect seen 

 feeding in small colonies on the twigs and branches. 



Control Measure 3 (end of circular). The spray should be 

 applied with force and repeated in 2 weeks. 



POTENTIAL INSECT ENEMIES 



There are several important shade tree pests that have not 

 yet, but may, become destructive in Illinois. Everyone should be 

 on the alert for them. Anyone finding an insect fitting one of the 



Fig. 52. — Japanese beetle: adults. Both male and female adults are 

 principally metallic green in color and about a half inch in length. Each has 

 white spots on the tip of the abdomen. 



descriptions below should place the insect in alcohol and send it 

 to the Illinois Natural History Survey, Urbana. Early knowledge 

 of the presence of a new pest may result in holding down an in- 

 festation or in wiping it out completely. 



Japanese Beetle, Popillia japonica Newm., fig. 52. — The 

 Japanese beetle feeds on the foliage of a wide variety of trees, 

 shrubs, vines, and other plants. It is a ravenous feeder that oc- 

 curs in great hordes. 



A native of the Orient, this insect was first found in the 

 United States in 1916, and isolated infestations now occur in 

 Illinois. The adults, metallic green beetles about one-half inch 

 long, have white spots on the tips of their abdomens, just back 



