Page:Popular Science Monthly Volume 69.djvu/222

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218
POPULAR SCIENCE MONTHLY

The possibilities of the pedigree-culture are by no means exhausted with covering the above points, especially if the plants chosen for the objects happen to be capable of vegetative reproduction, that is by cuttings or slips, in which case comparisons should be made of progenies grown from seeds of the plant with wide leaves with individuals grown, from slips of the same, and also compared with others from the extreme end of the series.

It is by undiscriminating discussions of horticultural operations involving seed-selection and hybridization, followed by vegetative propagation, that the public mind has become confused as to the nature and

Fig. 3. Experimental Grounds showing Pedigreed Cultures of Œnothera in New York Botanical Garden.

possibilities of selection, notably by the 'popular' and pseudoscientific descriptions of the thorough work of Mr. Burbank. By successive selections certain features, such as size or quality, of a fruit are forced to a maximum development perhaps in a single plant, or may be in hundreds, after which the desirable quality is carried along, or propagated, in quantity by cuttings of the original plant, thus excluding a possibility of a return to the average habit of the species.

Or, in hybrid combinations and resolutions, the desirable constitution of some horticultural form may be secured only after the most highly complicated and repeated crossing, with a result too complex to be easily analyzed. With one desirable individual at hand which produces nuts, berries, cherries, apples, potatoes or plums, or timber, it may be made to produce hundreds and thousands exactly like it merely by using its buds and branches for grafting and budding or propagating.