As grown on varied soils, altitudes, and with varied heat and

length of summer, varieties vary exceedingly in season of ripening, coloring, and distinctive form and markings. As to season, many varieties that keep through winter east of the lakes become fail apples when grown on the darker and richer soils and in the drier and hotter summer air of the prairie States in the same latitude. The drier and hotter air also gives richer coloring to all varieties, as shown at the expositions in competition with the same varieties grown in cooler, moister climates.

Varieties that prove good keepers on their northern limits of growth also become late-summer or fall varieties when grown in the Southern States. This is specially true in the Mississippi valley. Many hardy varieties that keep well, if picked at proper time (136. Picking and Handling Winter Apples) on the 45th parallel, become late-summer varieties even in southern Iowa.

Many varieties of the apple also have proven local in their adaptation to a given soil and climate. The Esopus Spitzenburg, as an instance, was originated at Esopus on the Hudson, where it has been grown commercially for fifty years and the fruit exported to Europe on a large scale. It is still the favorite variety at Esopus, but is only double-starred by the American Pomological Society in four of the pomological districts of the Union, three of which are west of the Rocky Mountains. The Belmont heads the list near Cleveland, Ohio, and fails at Cincinnati. The Baldwin is a leading commercial variety, yet it is only double-starred in one pomological district east of the Rocky Mountains, running from the Atlantic west to Michigan.

The Ben Davis reaches its highest development in the dry, hot summer air of the southwest prairie States and in some of the arid States. But at present, on account of its hardiness, heavy bearing, and size and beauty, it is the one cosmopolitan winter variety grown more or less across the continent. A close study of the American pomological list will show that most varieties are relatively local in exact adaptation to soil and climate. In many cases varieties that fail to prove profitable in a given locality are materially benefited by top-working (89. Top-working the Apple) on stocks adapted to the soil and climate. In Europe this plan is understood and practised to an extent not yet reached in this country. Different stocks are used often in one vicinity, on account of the varied soils, exposures, and elevations. Professor Bailev says: "It must follow that the promiscuous and wholesale dissemination of a few varieties over the country must eventually cease and that local and special sorts must constantly tend to drive out the cosmopolitan and general varieties. In this country it is only in the strawberry that the peculiarities of adaptation of varieties to soils have begun to be well understood; and this is rather because the subject is forced upon the attention by the short generations and constantly shifting plantations of the plant than from any investigational motive." Section (139. Fruit-growing Neighborhoods) discusses the desirability of fruit-growing centres. In apple-growing for market, there is special gain in extended plantings in sections specially adapted to the development of some of the leading commercial varieties, as it leads to systematic orchard management and the handling and sale of the crop to the best advantage. It also gives an opportunity for saving apples that would go to waste by drying, canning, and cider- and vinegar-making.