34o POPULAR SCIENCE MONTHLY. 



of judgment, in which he excels all his contemporaries. The best proof 

 of this is to be found in the great success his creations have made, not 

 only in North America, but also in Europe. 



His methods of work are the same as those followed by plant breed- 

 ers in Europe. Secrets he has none, and if he is not willing to demon- 

 strate his cultures to everybody, this must be attributed to the fact that 

 his time is too valuable. There is no fear that any one could ' steal 

 his trade ' by merely looking at it. Every one is left free to follow in 

 his path, but without the special disposition for it nobody will succeed, 

 and for simple imitation the entire process is too complicated. 



To give an idea of the immensity of his cultures, it is sufficient to 

 cite one instance. When selecting a new kind of blackberry he picked 

 out the best from 60,000 specimens, all in full bearing, dug up the rest 

 and burned them. This is his way of working, not only with one kind 

 of fruit or flower, but with all. The most remarkable trait, however, 

 of his work is that he experiments with as many forms as possible. 

 This method is carried to the highest degree of perfection, and thereby 

 his results are so stupendous that they receive the admiration of the 

 whole world. 



However large may be the number of forms subjected to crossing 

 and selecting, this method is in itself limited. Burbank's products are 

 all, with a few exceptions, reproduced not from seed, but by vegetative 

 propagation. Grafts or cuttings, bulbs, shoots or division of roots are 

 the means of multiplication. It is well known that vegetative propa- 

 gation results in much greater stability than raising from seeds, which 

 often produces degenerate types. Because of this fact, Burbank hardly 

 ever experiments on annual or biennial plants, but confines himself to 

 perennials. 



In Burbank's methods selection plays the most important part. To 

 accomplish a good selection, however, the greatest possible degree of 

 variation is a prerequisite. This variation is attained mainly through 

 selection of the starting points and through artificial hybridization. 

 The results are next cultivated on a large scale under environmental 

 conditions which will develop as many differences as possible. 



Varieties coming from separate localities differ not only in regard 

 to external characteristics, but their capacity of modification varies 

 considerably, and can often be ascertained only in the special environ- 

 ments of an experimental garden. The greater this power of adapta- 

 tion the more chances for the experimenter. 



As a general rule, it holds true that the results of crossing depend 

 primarily on the selection of varieties used for that purpose. These 

 indicate, so to say, the program, the list of possibilities from which the 

 choice and the combinations have later to be made. Outside of this 



