This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1907 Excerpt: ... course, older, but they are only a small number in comparison with his present stock. The larger part of his experiments are younger, and only a few of his pedigrees cover more than ten years, as, for instance, those of the plums. A special feature of Burbank's work is the large scale on which his selections are made. It is evident that in a variety of mixed condition, or in the offspring of a hybrid, and even in ordinary fluctuating variability the chance of finding some widely divergent individual increases with the number of the plants. In some hundred specimens a valuable sport can hardly be expected, but among many thousands it may well occur. The result depends largely upon these great numbers. In one year he burned up sixty-five thousand two and three year old hybrid seedling berry bushes in one great bonfire, and had fourteen others of similar size. He grafts his hybrid plums by the hundreds on the same old tree, and has hundreds of such trees, each covered with the most astonishing variety of foliage and fruit. Smaller species he sows in seed-boxes and selects them before they are planted out, saving, perhaps, only one in thousands or ten thousands of seedlings. Thornless brambles, spineless cacti, improved sweet grasses (Anthoxanthum odoratum), and many others I saw in their wooden seed-boxes being selected in this way. The same principle prevails in the selection of the species which are submitted to his treatment. Here, also, the result depends chiefly upon the numbers. He tries all kinds of berries and numerous species of flowering plants. Some of them soon prove to be promising and are chosen, others offer no prospects and are rejected. The total number of the species he has taken into his cultures amounts to 2,500. The list of the introducti...