tivation and, careful selection have produced a number of forms with variously shaped thin shells, which are propagated by grafting and budding." (Silva, Vol. VII, p. 115.)
We now know how to breed plants, In the short space of a few years we can surpass the results of centurics of chance breeding. The plant kingdom has become almost as clay in the hands of the potter. Where we now have one good crop plant, we may some day have five or ten. We need to start in earnest to apply some of our science to producing genius trees—trees that are to other trees as human geniuses are to other men.
Genius trees produced either by chance or design can be propagated a million or ten million times as was done with the one chance navel orange tree.
THE TREE A BETTER CROP PLANT
We need a new profession, that of the botanical engineer, which will utilize the vital forees[1] of plants to create new mechanisms (crop yielding trees) as electrical and mechanical
- ↑ This creation of new types by plant breeding depends upon three facts—first, the variation of different offspring from the same parents; second, the varying combinations in offspring of the qualities of the parents: and third, the appearance in offspring, especially hybrid offspring, of qualities possessed by neither parent.
First, variation of offspring. Look at the children of almost any family you know. This tendency to variation runs deep into both animal and plant life. For example, Texas Agricultural Experiment Station, Bulletin 349, "Variation in certain lint characters in a cotton plant and its progeny" shows that the average length of lint in the individual plants of the progeny of a certain boll (seed pod) varied from 19 millimeters to 285 millimeters, a variation of 50 per cent. This is very suggestive of the way by which through a selection of parents we have changed the cow so marvelously for milk production. The object of selection here is to find desirable strains that produce uniform progenies. Page 15 shows that tree breeding has a more easily attainable objective—namely, one good specimen.
Second, varying combinations in offspring of qualities of parents. A hybridization of hazels and filberts (Fig. 20) produced plants ranging from 12 inches to 12 feet in height—suggestive of variations in great degree for each quality a plant can have.
Third, the appearance in hybrid offspring of qualities possessed by neither parent. Some of the above-mentioned hazel x filbert hybrids bore
