INSECT PESTS OF OHIO SHADE AND FOREST TREES 293 



may be expected in May or early June and the second one of the 

 season in late summer. 



THE HONEY LOCUST SCALE 



(Chionaspis gleditsiae Sanders) 



Description. The scale of the female of the honey locust scale 

 is thin, fragile, frequently covered with a sooty secretion and is 

 but little more than one-sixteenth of an inch in length. In heavy 

 infestations the bark of the host presents a dark-gray appearance 

 as if weathered newspapers were pasted snugly over it. The male 

 scale is smaller, white, and distinctly ridged. (See Plate L, Fig. 1.) 

 The eggs are purplish-red, and it is in this stage that the winter 

 is passed. 



Nature of work. The principal injury is to the bark of the 

 host, and while the writer has never seen a case where an attack 

 could be said to be fatal, yet the sapping by the insects decreases 

 vitality and retards growth. Not infrequently control measures 

 are advisable in the case of shade and park trees. 



Food plant. The honey locust (Gleditsiae triacanthos) is the 

 only host recorded. 



Distribution. This insect has been taken in extreme south- 

 western and extreme northeastern Ohio, as well as in many inter- 

 medial points both in woodland and artificial plantings, hence it 

 seems safe to assert it is likely to be found wherever its host grows. 

 Outside of Ohio the species has been reported from Indiana (42) 

 and Mississippi (43) . It is to be expected therefore that the species 

 has a rather wide distribution. 



Natural enemies. Hymenopterous parasitism is common, but 

 the writer has not bred out the adult form. 



Control. One experiment only has been conducted by the 

 writer by way of testing artificial control measures for this species 

 and that involved the use of the soluble sulphur compound. This 

 material was used at the rate of 13 pounds to 50 gallons of water 

 and was applied to badly-infested honey locust in Eden Park, Cin- 

 cinnati, Ohio, March 29, 1915. The control was absolute. Since it 

 has been our experience with other species that the other sulphur 

 sprays will control the forms controlled by the soluble sulphur com- 

 pound, it seems reasonable to expect the same perf omance in regard 

 to this species. 



THE ETJONTMUS SCALE 

 (Chionaspis euonymi Corns t.) 



Description. Although the euonymus scale is one of the true 

 scurfy scales, the female scale resembles that of the oyster shell 



