The most valuable native species of the United States is Pyrus coronaria. As found in the prairie States it differs some in habit of tree and flower and fruit, and Professor Bailey has given it as a distinct species under the name of Pyrus Ioensis. This race as found in the early days of prairie settlement in the hazel-thicket borders of native timber belts varied in habit of growth, leaf, and size of fruit fully as much as our native plums. Some of the selected varieties attain fair apple size under cultivation. On the college grounds at Ames, Iowa, can be seen a tree loaded every year with fruit over two and one half inches in diameter and of nearly the shape of a medium-sized Rhode Island greening. This variety is known as the Fluke crab. Mr. B. A. Mathews, of Knoxville, Iowa, grows for market a variety fully as large as the Fluke. In fact, in about every neighborhood of the prairie States - especially in Iowa - can be found isolated trees and sometimes several trees together of these large-fruited varieties. Professor Bailey expresses the belief that these varieties, with leaves approaching in size and structure those of the common apples, are hybrids with the latter class. But this cannot be true, as in the early days (185G) on the writer's farm in Benton County, Iowa, several trees on a thicket border bore bright yellow crabs larger in size than any Soulard we have since grown, but not quite as large as the Fluke. At that early date there was not a bearing apple-tree in that vicinity, and the trees bearing the large yellow apples dated back to the years when the buffalo ranged over Iowa prairie.
These select varieties attain quite large size under cultivation. On the college farm at Ames may be seen two trees of Soulard that are larger in stem and have greater spread of top than any Duchess apple-tree of their age in this region. But the quality of fruit of these large-fruited varieties is not as varied as has been claimed. All of them have the smell and flavor of the wild crabs of our thickets.
As to improvement in size and quality by crossing with cultivated varieties our long experience is given in section (106. Violent Crosses). In all cases we were able to secure crossed fruits, as was evidenced by change of form, but without a single exception the fruits were destitute of perfect seeds. All attempts to bud or graft it with scions of our cultivated apple have resulted in poor union of the woods, soon broken off by storms. The Bethlehemite for a time seemed an exception. Top-worked on the native crab this variety soon came into bearing and at first the fruit was of the usual size and flavor. But the size in four years became smaller and the flavor was decidedly disagreeable, resulting, as afterwards ascertained, from poor union of the wood of the two species.
By culture and selection it is now evident we can increase the size of our best varieties, but the peculiar perfume and a stringency of flesh will be apt to be retained in large part for many years. Yet in the quite-distant future we may develop from this hardy species a race of apples that will become favorites for many purposes and possibly for dessert use. At this time Mr. B. A. Mathews, of Knox-ville, Iowa, grows the Mathews crab for market, and reports that he sells it for one dollar per bushel when orchard varieties are selling for from fifty to seventy-five cents. But the use made of them by purchasers is to mix with common apples for culinary use to impart a quince flavor.