New York Agricultural Experiment Station. 581 



black ash, iron wood {Ostryia)^ and golden rod. In the case of the 

 golden rod the infested plants were growing in a badly infested 

 grove of black ash trees. The writer has found the scale infesting 

 the following varieties of plnm : Lombards, Bradshaws, Quacken- 

 boss, Prune, Shippers' Pride, Myrabolam, Yellow Egg, Washington, 

 Empire, Hudson River Egg, and Union Purple. In every infested 

 orchard examined, which includes six large ones and one compara- 

 tively small one. the scales were always more abundant on some one 

 or two or all of the hrst three varieties named, than upon any of the 

 others. 



Although the scale is at preser^t chiefly a plum pest, it has lately 

 infested quince orchards sufficiently to cause alarm, and has been 

 found in apple trees in sufficient numbers to do serious injury. 



Will the scale attack nursery stock ? — During the winter of 1894-95 

 we had occasion to examine plum stock ranging in age from one to 

 three years in nurseries at Geneva, Rochester and Syracuse, but failed 

 to And the scale, excepting in one case where a few scales were found 

 on a number of three-year old plum trees which were heeled in in 

 the nursery waiting to be sold. In one nursery there were a num- 

 ber of badly infested plum trees along a wagon path between blocks 

 of young plum stock, but no scales could be found upon the stock. 



In addition to examining the stock we have made numerous in- 

 quiries among nurserymen, but have failed to find an instance, with 

 the above exception, where the scale has been found upon nursery 

 stock. 



How do the Scales Spread f — This question is one which is often 

 asked and receives many different answers. There may be several 

 ways. It is possible that birds aid by carrying the young female 

 scales on their feet from one tree to another, or from one orchard to 

 another. Larger insects, such as certain of our lady bird beetles, 

 have been found with young scales crawling about on them, thus 

 giving opi)ortunity for transportation from one tree to another by 

 this means. They may also easily get on the clothes of workmen 

 who are in the orchard when the scales are active during the sum- 

 mer or fall, or they may be carried from one place to another on 

 the boxes, baskets, wagons, etc., used in the orchard at various times. 

 Another means of travel is undoubtedly upon the leaves which are 

 blown from the trees during the summer and scattered about through 

 the orchard. During the winter the young scales may frecp.iently 

 be found upon the old dead leaves scattered through the orchard. 



