298 OHIO EXPERIMENT STATION: BULLETIN 332 



First, this species is not as prevalent and, second, the leaves only 

 of the host are greatly affected while its near relative attacks the 

 more important twigs. Occasionally, however, it demands treat- 

 ment. 



Food plants. — But two hosts, the soft maple (Acer sacchari- 

 num) and the sugar maple {A. saccharum) are reported for this 

 species. 



Distribution. — Apparently this scale is a native American 

 species. It has been reported from Massachusetts, New York, New 

 Jersey, District of Columbia, Tennessee, Ohio, Indiana, and some 

 of the western states. 



Natural enemies.- — The lady-beetle, Hyperaspis signata Oliv., 

 a .small fly, Leucopis nigricornis Egger, and the following list of 

 hymenopterous parasites have been reported as destroying this 

 pest: Aphycus Eederaceus Westw., Aphycus flavus How., Coccopha- 

 gus fraternis How., Pachyneuron altiscuta How., and Chiloneurus 

 alhicornis How. 



Control. — The same control is recommended for this species as 

 was given for the cottony maple scale. 



THE MAPLE PHENACOCCUS 



(Phenacoccus acericola King) 



Description. — Quite frequently the maple phenacoccus is mis- 

 taken for the cottony maple-leaf scale, just described, since both 

 appear upon the underside of maple leaves, but the two may be 

 differentiated with ease, since the present species appears as an 

 irregular cottony mass, about one-fourth of an inch in diameter, the 

 cottony secretion completely covering the insect's body and egg 

 mass, while the cottony maple-leaf scale appears as a distinct fluted 

 ovisac with the brown body of the insect attached at one end. Com- 

 pare Figures 3 and 5 of Plate LII. At certain seasons of the year 

 the young, crawling females and the white cocoons of the males may 

 be found in great quantity upon the trunk of badly infested trees. 

 (See Plate LII, Fig. 4.) 



Life history and habits. — The partially-grown crawling scale 

 insects pass the winter within the shelter of crevices in the tree 

 trunk, emerging the following spring and migrating to the underside 

 of the leaves. They mature and deposit upon an average of about 

 500 eggs in the white, cottony egg-covering. These eggs hatch and 

 the cycle is repeated two or three times during the summer. 



Nature of work. In the writer's experience this insect has 

 never been observed inflicting great harm in Ohio, though a few 

 instances have come to his attention where individual trees were 



