The Canadian Horticulturist. 155 



pointed knife will soon discover the hateful intruder, which will be at once seen 

 to be truthfully represented in Fig. 948 b, with its great flat head, which is 

 altogether out of proportion to its body. Washing the trunks of the trees at 

 this season with some alkaline solution of washing soda and water, the latter in 

 the proportion of a quarter of a pound to a gallon. 



Another formula — Take one quart of soft soap boiled in two gallons of 

 water, and while hot stir in one pint of carbolic acid. 



The Oyster Shell Barklouse is insignificant in size, but terrible by reason of 

 its numbers Very few have any idea how common a pest this is in our Cana- 

 dian orchards. Many people are wondering why their orchards are so unfruitful, 

 and why they are so stunted in growth, and look so sickly, when the whole 

 trouble is due to this pernicious little louse, which, unnoticed by them, is prey- 

 ing upon the bark of their apple trees in immense numbers, sucking out their 

 strength and life. 



Once toward the end of May a neighbor brought in to the writer a branch 

 of a young tree from his orchard asking, "What is the matter with this tree?' 

 The tree would not grow, and he had discovered that the bark was curiously 

 rough with numerous tiny scales about one-sixth of an inch in length, 

 Upon lifting one of these scales and using a hand glass the question was soon 

 solved. To his astonishment, there were revealed nearly one hundred wee 

 little lice, too small to be readily seen by the naked eye, and which ran about 

 with the greatest speed over the bark as if delighted at their liberation from 

 the confinement of the material shell. No wonder the tree was stunted ! 



This louse belongs to the genius Coccidce, and is allied to the aphis, bedbug, 

 and body-louse. It was introduced into this country some eighty years ago 

 from Europe, and although the female cannot fly, and hence migrates slowly, it 

 has now become more or less distributed throughout our whole country. 



The time to destroy these bark lice is early in the month of June, because 

 at that time the younger brood escape from under the scales where they hyber- 

 nate, and which are actually the dead bodies of the mother lice. The loose 

 bark should first be scraped off with a hoe, because the cunning youngsters hide 

 away carefully beneath it, as if they were trying to escape discovery. 



The trunks and large limbs must be washed with a strong solution of soft 

 soap and washing soda, with enough water to enable one to apply it with a paint 

 brush, or scrubbing brush. If the lice have spread over the limbs, the whole 

 tree must be sprayed with a solution of washing soda and water in the propor- 

 tion of half a pound to a pailful, or potash and water, two pounds to seven 

 quarts. Caustic soda and water is recommended as still more effective. 



There are several insects which prey upon the bark louse, as also some 

 insectivorous birds, but unfortunately this hateful insect increases out of all pro- 

 portion to the number of its destroyers, and unless vigorous remedial measures 

 are employed, some of our best orchards will die of premature old age. 



