340 Wisconsin State Horticultural Society. 



foes lurking there. There is little doubt as to the efficiency of 

 this remedy when used in sufficient quantiiies, but, for several 

 reasons, it is not likely to come into general use. If applied too 

 freely, it is said to injure the roots; its offensive odor would deter 

 some from handling it, others would consider its inflammability 

 and explosive character sufficient reason why its use should be 

 avoided; while the still weightier reason of its expense stands in 

 the way of its very general use. 



Those insects which a&'ect the trunk and branches of trees are 

 either borers which burrow under the bark or bore into the solid 

 wood, or bark lice of various species, which fasten on the grow- 

 ing twigs and suck the juices therefrom. For the former, when 

 they have once found a lodgment in the tree, we can suggest no 

 better remedy than that of searching them out and destroying 

 them, but much may be done to prevent their attacks. In each 

 case the parent insect deposits her eggs on the bark, usually in 

 little crevices, formed by irregularities in the surface, and when 

 hatched, the young larva at once commences to eat through the 

 outer bark to the interior. Alkalies, such as potash and soda, 

 also alkaline earths, such as lime, are very destructive to insect 

 life, and, by coating the bark with a suitable alkaline solution, at 

 the proper season, either the insects will be deterred from deposit- 

 ing their eggs thereon, or the eggs or young larvae will be de- 

 stroyed. A suitable solution for this purpose may be made by 

 adding to a gallon of soft soap about half a gallon of a strong so- 

 lution of washing soda, as much as the water will dissolve. This 

 solution, which will be about the consistency of paint, should be 

 applied sometime early in June, selecting a fine dry day for the 

 work, when the solution, on drying, will form a sort of alkaline 

 varnish not readily washed off by rain. If thought desirable, 

 the application may be repeated a month later. The mixture of 

 lime and sulphur, recommended as a preventive for fire blight in 

 the pear, would probably serve an equally good purpose, and ap- 

 plied to pear trees might do a double service. The same appli- 

 cations would be efficacious in removing bark lice, but for this 

 purpose should be applied to the affected branches earlier in the 

 season, just as the buds are bursting, as that is the time when the 



