288 OHIO EXPERIMENT STATION: BULLETIN 332 



The application of control measures is rarely if ever feasible 

 under woodlot conditions, for the expense of the operation far 

 exceeds the results obtained since woodlot trees are usually high 

 and the cost of treatment correspondingly great. 



THE SCURFY BARK LOUSE 



(Chionaspis furfura Fitch) 



The scurfy bark louse and the oyster shell bark louse are quite 

 commonly associated, but of the two the latter is the more serious 

 pest, first, because it attacks a wider range of host plants, second, 

 because it is more destructive in its action, and, third, because it 

 is more difficult to control. 



Description. The male and female scales of the scurfy bark 

 louse vary greatly in appearance. The female scale is pear-shaped 

 in outline, is almost flat and is about one-tenth of an inch in length. 

 Scales found in woods away from dust and smoke are almost pure 

 white with a yellow tip, but when found in cities and in situations 

 where foreign particles collect upon the surface, they vary in color 

 from light to very dark gray. The surface is dull, not glossy. 



The male scales are much smaller with almost parallel sides and 

 the surface is broken by three ridges extending lengthwise. They 

 too are white under sanitary conditions and darker in the presence 

 of smoke, dust, etc., but are not so seriously discolored under similar 

 conditions as are the female scales. The mature female insect is 

 without appendages, sacklike and is not motile. The male scale 

 is winged and very fragile. (See Plate XLVIII, Fig. 3.) 



The eggs are minute, reddish-purple and are found beneath the 

 protection of the mother scale. Quaintance and Sasscer (40) found 

 that the average of eggs of 20 individuals was 57 eggs each. 



The young are minute, reddish and are motile for a short time 

 after hatching. 



Life history and habits. The winter is passed in the egg stage 

 beneath the shelter of the female scale. The eggs hatch during 

 late May or early June and the young move about actively for a day 

 or two, whereupon they settle on the host, begin feeding and form 

 the scale covering. By late summer the sexes have matured; the 

 female deposits her quota of eggs and dies, and her body shrivels 

 up into the dark, misshapen object one finds beneath the narrow 

 point of the scale. 



There is but one full brood in Ohio, but a partial second brood 

 may occur. 



Nature of work. To young trees or trees of low viltality, the 

 injury by this species is severe, sometimes causing the death of the 



