31 



California in the hope of finding a variety which would be " cur- 

 culio proof," and the scale was probably brought east on this stock 

 and spread all through the nurseries referred to, both of which did 

 a large wholesale business in the eastern and middle States. Stock 

 sent out was therefore infested by this scale, which spread in the 

 nurseries to which it was sent, and thence went out in the retail 

 sales to all parts of the country. With such methods of distribu- 

 tion it is no wonder that this scale is now working destruction in 

 nearly every one of the United States, and in Canada and foreign 

 countries. In Massachusetts it is now known to occur in over a 

 hundred cities and towns, often causing much loss, and it is prob- 

 ably present in many other places from which it has not as yet 

 been reported. 



Food Plants. 

 This scale seems able to live on almost any plant, but is of 

 little importance on those which die to the ground each winter, as, 

 when this happens, any scale on the dead part also dies, and it 

 does not appear to locate below the ground. It seems to prefer 

 for its food plants of the botanical family Rosacese, for it thrives 

 best and becomes injurious to plants of that group, with a few 

 exceptions, more quickly than on those of any other group. As 

 the Rosaceae includes most of our fruit trees, small fruits, roses, 

 thorns and Spiraeas, and as the scale is also a serious enemy to 

 currants, gooseberries and grapes, nearly all our fruitbearing 

 trees and plants are included in the list of its favorite food plants. 

 It is also found on elms, maples, birches, willows, poplars and 

 many other trees and shrubs, and has once been reported on 

 spruce and arbor vitce, but in these cases it is doubtful if it 

 often thrives sufficiently to kill the plant it is on. When it occurs 

 on such food plants, however, it is no less a menace, as from them 

 it may spread to other trees and shrubs in the neighborhood, less 

 resistant to its attacks. 



Description and Life History. 



The adult female insect is lemon yellow in color but is covered 

 by a hard dead scale, which is circular in outline, slightly raised 

 in the centre, forming a sort of nipple, and is about the size of a 

 pin head. Beneath the scale the insect lies, with its beak thrust 

 into the plant till it reaches the sap on which it feeds. The scale 

 being dead and closely fitting the surface of the plant at its edge, 

 it is impossible to reach and kill the insect beneath by any of the 

 milder washes. 



The winter is passed under the scale in this condition, but the 

 very young and adult insects appear to die during this time. In 



