HOG HAW (_Cratægus brachyacantha_) is distinguished by its blue fruit. The name indicates that the fruit is unfit for human food but is eaten by swine. In some parts of Louisiana the dense thickets produce considerable quantities of forage for hogs. The range is not extensive, being confined to Louisiana and eastern Texas where the tree occurs in low, wet prairies. The largest specimens are forty or fifty feet high and eighteen inches in diameter. It is one of the largest of the thorns, and the best trunks are of size to make small, very short sawlogs, but it does not appear that the wood has ever been manufactured into commodities of any kind. The tree is occasionally planted for ornament. BLACK HAW (_Cratægus douglasii_) reaches its best development on the Pacific coast where trees occur thirty or more feet in height and a foot and a half in diameter. The principal range is west of the Rocky Mountains, from British Columbia to northern California, but it extends eastward to Wyoming, and the tree is found also in northern Michigan. The fruit is black or very dark purple, is edible, and matures in early autumn, falling soon after. The heartwood is brownish-red. No use for the wood has been found on the Pacific coast. WASHINGTON HAW (_Cratægus cordata_), also known as Washington thorn, Virginia thorn, heart-leaved thorn, and red haw, grows on banks of streams from the valley of the upper Potomac river southward through the Appalachian ranges to northern Georgia, and westward to Missouri and Arkansas. Flowers are rose-colored, the fruit ripens in the fall and hangs till late winter. Trees are twenty or thirty feet high, and a foot or less in diameter. Washington haw is frequently planted in this country and in Europe. ENGLISH HAWTHORN (_Cratægus oxyacantha_) was introduced into this country from Europe and has become naturalized in some of the eastern states. Thirty or more varieties are distinguished in cultivation. It is worthy of note that, although the United States has more than 130 species of thorn trees of its own, with varieties so numerous that no one has yet named or counted all of them, a foreign thorn has been introduced and added to the number. [Illustration] MAHOGANY [Illustration: MAHOGANY] MAHOGANY (_Swietenia Mahagoni_) This tree belongs to the family _Meliaceæ_ which has about forty genera, all of which are confined to the tropic except _Swietenia_ to which mahogany belongs. This tree has made its way up from southern latitudes and has secured a foothold in Florida where it is confined to the islands and the most southern part of the mainland.