CHAPTER VI 



CONTROL OF PARASITES 



E have seen in previous chapters the character 

 and effect of parasitic attacks on trees, how 

 they are recognized, and also that their dam- 

 age can be checked and reduced to a large 

 extent by the mere care of keeping the trees in vigor. We 

 are now to consider specific methods of controlhng these 

 fungus and insect injuries. 



Fungus Parasites. The fundamental principle in com- 

 bating fungus attacks is to prevent the infection of the host 

 plant by the spores, or else to destroy these through the 

 application of antiseptics or poisons, — so-called fungicides. 

 But, if infection has already taken place, the spread of the 

 disease is prevented by the destruction of the fruit-body 

 of the fungus when formed, thereby reducing the crop of 

 seeds, and also by burning the litter on the ground in which 

 the fungus may live during one phase of its development. 

 Careful pruning and painting of all wounds will prevent 

 the location and sprouting of the spores of fungi. If this 

 has been neglected or delayed, and an examination (under 

 the magnifying glass or microscope) shows that the mycelia 

 of fungi are already developed, the parasite may still be 

 suffocated, if the mycelium has not progressed too far, by 

 applying an antiseptic, like carbolineum, which, especially 

 if hot, will penetrate for some distance, and then covering 

 the wound with a heavy coat of paint, so as to exclude air 



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