112 



REPORT OF 



No. 10 



years lias attracted so nmch attention, and so many enquiries have been re- 

 ceived concerning the best methods for its eradication, that it is hoped earnest 

 efforts will be made at once by all concerned to get it under control. 



The Oyster-shell Bark-louse (Mytilaspis pomorum or Lepidosaphes ulmi 

 Linn, as it is now called) is widely scattered throughout the orchards of On- 

 tario, and the damage done by it is very considerable over the Province and 

 rapidly on the increase. 



Fig. 32— Trombidium i.ocustarum— (a) female with her hatch of eggs : 



(6) newly-hatched larva— natural size shown by the dot in a circle 



on the right; (c) egg; (d, f) empty eggs-shells (after Riley.) 



Although of European origin, it has been known in America for more 

 than a century, and has gradually spread throughout the larger portion of 

 North America. 



This scale is a very serious pest in orchards which are neglected and 

 badly treated, but experience has shown that with careful treatment it can 

 be readily kept in check. It has been found to occur on the following trees 

 and shrubs: Apple, plum, pear, wild red cherry, grape, currant, rose, maple, 

 poplar, ash, birch, and various others. 



Fig. 33— The Oyster-sheil Bark-louse. 



In order to combat this scale, it is first absolutely necessary that one 

 should be well acquainted with its life-history. 



Life-history. — This minute insect, found upon the bark of the small 

 twigs and also upon the branches and trunks of the above-mentioned trees, 

 is readily identified by its oysler-shell-shaped scale, about one-sixth of an 

 inch in length. It is of a brown colour, and, thus disguised by the bark, 

 is not seen unless by close observation. Usually a good many are clustered 

 together, and their shape is so marked that orchardmen should soon recog- 



