REPORT ON FORESTS. 231 



In general, birds are the foresters' friends, and should be 

 encouraged ; but I am not so sure about the woodpeckers. If 

 there be no dead or dying trees no woodpeckers are needed to 

 destroy larvse, and on the other hand there is little likelihood 

 that any will remain about where no chance for food-supply 

 exists. 



Frogs, toads, lizards and snakes are great entomologists, and 

 destroy vast quantities of insects without in turn causing injury, 

 lyizards, especially, destroy large numbers of wood-feeders, and 

 should be encouraged. 



Sometimes high winds, lightning or other causes injure or 

 kill a branch or break it without harming the main tree, but 

 leaving perhaps a ragged stump in case of breakage. All dead 

 wood of this kind should be cut out, and all ragged stumps due 

 to breakage should be properly trimmed off. 



Direct insecticide applications are rarely practical in forest 

 work, though in parks, where the trees have an ornamental 

 value, they may become desirable. Against borers no applica- 

 tions can be made. The preventive measures already mentioned 

 will suffice for them. The pruners or girdlers may be checked 

 by systematically gathering and burning all the fallen branches 

 in winter. This is really necessary on park land only, for the 

 pruning done in the forest under normal conditions amounts to 

 nothing, and natural enemies prevent too great an increase in 

 the species. Isolated trees scattered in open groves are much 

 more severely injured, and in such cases the gathering and burn- 

 ing of the pruned branches is indicated. 



Where leaf feeders really endanger the tree or its foliage, 

 particularly conifers, arsenate of lead will prove the best insecti- 

 cide for general use, because of its harmlessness to foliage of all 

 kinds. 



Arsenate of lead is made by dissolving in water, in separate 

 vessels, 4 ounces arsenate of soda and 11 ounces acetate of lead. 

 The amount of water is immaterial, so it is sufficient to com- 

 pletely dissolve the chemicals. When the solutions are com- 

 plete, combine the two and add water to make 80 gallons. This 

 will kill most leaf-feeders in their early stages ; but if the larvse 

 are well grown, or if adult beetles are to be dealt with, 40 

 gallons will be enough to use. 



