OUR RIVALS 135 



But all this while the vegetable world is out of 

 harmony with us, that is with our control, and fungus 

 diseases are at work more dangerous even than 

 insects. We must begin our contest with this sort 

 of rivalry very early in the spring and it must go on 

 through the whole year. No one can tell just when 

 there will be a sudden development of some form of 

 parasitic growth. 



The spores that make plum knot scatter and plant 

 themselves late in the fall, or even in the winter. 

 These grow with immense rapidity, and your whole 

 orchard will be covered in a single season. This 

 must be fought with a sharp knife, cutting above and 

 below the knot, and sometimes sacrificing a whole 

 tree. It is a pleasant fact that some sorts of plums 

 are entirely immune. Pear tree fungus comes in the 

 form of blight and is imperceptible to the human 

 eye until large limbs or whole trees are done for. 



Spraying with Bordeaux mixture is a general pre- 

 ventive of these fungoid developments, and it is a 

 good thing, very late in the fall, to give a good spray- 

 ing to every fruit tree you have. It will do no harm 

 if applied in the winter better yet very early in 

 the spring, before foliage starts. However, there 

 are many fungi that cannot be either prevented or 

 cured by this remedy. 



Your apple and pear trees with scabby bark must 

 be thoroughly washed or sponged, once a month, 

 with strong kerosene emulsion and Bordeaux mix- 

 ture. This will kill the fungus and stimulate healthy 



