352 LUTHER BURBANK 



that may obtain still greater heights by the still 

 more intelligent utilization of these forces. So 

 it will be accepted as a mere matter of course 

 that we should attempt, in completing the review 

 of this work with the development of new forms 

 of plant life, to make application of the practical 

 knowledge gained in the experiment garden to 

 what might, without violence to words, be 

 described as the breeding of the human plant. 



Such an application we shall now attempt, 

 concisely, yet with as much explicitness as is 

 warranted. 



tTHE Great Principle of Selection 



Even the most casual reader of this work 

 will be aware that the great fundamental prin- 

 ciple that guides us in all stages of our experi- 

 ments in plant development is the principle of 

 selection. 



We select first the kind of plant that is to be 

 utilized in a given series of experiments. We 

 select the best individual or individuals to be 

 found among the entire company of these plants 

 at our disposal. We select other individuals of 

 the same or of different species as mates before 

 crossing, and in successive generations we repeat 

 these processes of selection and reselection over 

 and over. 



