CHAPTER VI 
CONTROL OF PARASITES 
al\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 controlling 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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