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STATE HORTICULTURAL SOCIETY. 



Remedy. — Borers are a difficult class of insects to deal with, as digging 

 them out after they have entered a tree is a treatment too severe to be 

 practiced if it can be avoided. The best success is found in the use of a 

 repellant, or some form of mechanical coating at the time the eggs are 

 laid. The carbolic acid and soft soap wash and arsenated lime as a paste 

 or whitewash are the two most likely to give satisfactory results. Which- 

 ever is used, the application should be made early in June and a second 

 three weeks or a month later, first clearing off the rough, loose bark. 



In applying either of these remedies, a scrub brush does the best work 

 in covering the bark, as it pushes the material into the crevices where the 

 borer usually deposits the eggs. 



THE OYSTER-SHELL BARK LOUSE {Mytilaspis pomorum Bon.). 



Very few orchards in Michigan are free from this pernicious little sap- 

 sucking scale. While it is attached to the bark, all that we see of the 

 louse is the minute scale-like covering which it secretes over itself. Upon 

 lifting the scale, the louse or its eggs can be seen by the aid of a lens. 

 From fifteen to one hundred eggs remain over winter under each scale. 

 In May or early June these eggs hatch into minute yellow lice that soon 

 leave the shell and enjoy a life of freedom for a few days, when they 

 become permanently located, insert their beak for the sap on which they 

 feed, and soon begin to secrete a shell of wax over themselves, never to 

 leave it again. By August the female has filled her shell with eggs, and 

 dies, the eggs remaining in the shell over winter. 



Fig. 9.— Oyster-shell Bark Loase; 2, yoang lonse magaified; 3, secreting wax coTering; 5 and/ 6, 

 louse without ^scale ; 7, louse in scale, underside;.?, scales on bark, natnral size. 



Remedy. — Scrub the trees with carbolic acid and soap inixture in the 

 spring or spray with kerosene emulsion in May when the young lice are 

 running. 



