Plums of Chinese, Korean, and Siberian Types
Encouraged by his early success, Mr. Burbank kept on importing Asiatic plums. He found these for the most part inferior in size and in quality to the American wild plums, but they furnished the bases for further experiments. The plums at the bottom of the picture represent improved varieties of the original type; and the larger plums above are accidental hybrids produced from pollenization effected by the bees with neighboring species.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 5 Chapter 2