LUTHER BURBANK 
pear does not really need so much water as it or- 
dinarily receives. 
But the effort to give the tree immunity must 
go even deeper. Induced immunity is valuable, 
but the ideal condition is that of inherent resist- 
ance, bred in the tissues. 
Physicians tell us that the all-important thing 
in warding off bacterial infections in the human 
subject is the inherent vitality and resistance of 
the patient himself. In the last analysis, this is 
the prime essential. A thoroughly rugged organ- 
ism may be immune to almost every type of bac- 
terial disease. We are told that almost no one 
escapes infection with the germs of tuberculosis. 
The ones who show no evidence of the disease are 
simply those whose tissues are so resistant that 
the attacks of the bacilli are thwarted. 
The horticulturist must take a lesson from the 
experience of the physician, in particular with 
regard to the malady we are now considering; for, 
as we have just seen, the analogy between the pear 
blight and human infections is almost perfect. 
So the ideal at which the plant experimenter must 
aim is the development of a tree that will be im- 
mune to the attacks of the bacillus, however freely 
the germ finds access to it. 
My new hybrid pear, thanks to its Oriental 
heritage, seems to fulfil this condition. The same 
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