Page:Tree Crops; A Permanent Agriculture (1929).pdf/166

 FACTS ABOUT CROP TREES Another way to restore our chestnut orchards and forests is for the plant breeder to create the desired varieties. There is a promising collection of varietal material now at hand in the Chinese chestnut (castanea molissima), one or two other species of Chinese chestnut, the Japanese chestnut (c. cre- nata), and in one American variety, the chinquapin (castanea pumila), which, strange to say, is perfectly immune to the blight. The chinquapin offers an interesting element for the plant breeder in that it has sweetness to a high degree, while the Japanese nuts are large and coarse like a raw sweet potato. However, latest reports seem to indicate that there are or- chard varieties of Chinese chestnuts, large, of good quality, and not yet introduced into the United States. 120 The theory of plant breeding depends upon (1) the fact of variations of individuals within the species or within the crossing range, and (2) crossing to get new combinations of qualities. The amount of variation among trees of the same species is a surprise to most laymen. One of the qualities in which trees differ is that of precocity. Those who think of all nut trees as being so very slow in coming into bearing may be amazed at the precocity shown by some trees as reported by Dr. Walter Van Fleet, at one time experimentalist for the Rural New Yorker and later with the Department of Agricul- ture. Dr. Van Fleet wrote to me on April 13, 1914, giving the following surprising results of a series of experiments in get- ting a precocious strain of Japanese chestnuts: No. 1. 1898. Japanese chestnut seeds planted. No. 2. 1902. Fruit produced by trees from No. 1. No. 3. 1903. Cross pollination of earliest ripening trees of No. 2. No. 4. 1904. Cross pollinated nuts of No. 3 planted. No. 5. 1906. No. 4 bore fruit, immediately planted. No. 6. 1909. No. 5 bore fruit profusely (in 3 years)-im- mediately planted.