Page:Tree Crops; A Permanent Agriculture (1929).pdf/39

 engineers use the forces of electricity and the elements of mechanics to create new mechanisms for the service of mankind.

For breeding experiments the tree has one great advantage over most of the annuals. We propagate trees by twig or bud, by grafting or budding. Therefore, any wild unstable (though useful) freak, any helpless malformation like the navel orange which cannot reproduce itself, can be made into a million trees by the nurseryman. With corn, oats, or alfalfa the breeder must produce a type true to seed before the farmer can use it.

Not only is the tree the great engine of production, but its present triumphant agricultural rivals, the grains, are really weaklings.

All plants require heat, light, moisture, and fertility. Give these things and the tree raises its head triumphantly and grows. But in addition to these requirements the weakling grains must have the plow. A given area may have rich soil and good climatic conditions, but be unsuitable for grain if the land happens to be rocky. Nor are steep lands good farm lands for grains. Trees are the natural crop plants for all such places,

Moreover the grains are annual plants. They must build