If you wish to raise new varieties of apples, it is quite possible to do so without practicing cross-fertilization. The cultivated varieties are so mixed in their heritage that nothing more is necessary than to plant seeds of almost any variety to secure a great number of aberrant new types. The ones here shown are seedlings of the Winterstein.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 4 Chapter 6