HICKORY, a shortened form of the American Indian name _pohickery_. Hickory trees are natives of North America, and belong to the genus _Carya_. They are closely allied to the walnuts (_Juglans_), the chief or at least one very obvious difference being that, whilst in _Carya_ the husk which covers the shell of the nut separates into four valves, in _Juglans_ it consists of but one piece, which bursts irregularly. The timber is both strong and heavy, and remarkable for its extreme elasticity, but it decays rapidly when exposed to heat and moisture, and is peculiarly subject to the attacks of worms. It is very extensively employed in manufacturing musket stocks, axle-trees, screws, rake teeth, the bows of yokes, the wooden rings used on the rigging of vessels, chair-backs, axe-handles, whip-handles and other purposes requiring great strength and elasticity. Its principal use in America is for hoop-making; and it is the only American wood found perfectly fit for that purpose.
The wood of the hickory is of great value as fuel, on account of the brilliancy with which it burns and the ardent heat which it gives out, the charcoal being heavy, compact and long-lived. The species which furnish the best wood are _Carya alba_ (shell-bark hickory), _C. tomentosa_ (mockernut), _C. olivaeformis_ (pecan or pacane nut), and _C. porcina_ (pig-nut), that of the last named, on account of its extreme tenacity, being preferred for axle-trees and axle-handles. The wood of _C. alba_ splits very easily and is very elastic, so that it is much used for making whip-handles and baskets. The wood of this species is also used in the neighbourhood of New York and Philadelphia for making the back bows of Windsor chairs. The timber of _C. amara_ and _C. aquatica_ is considered of inferior quality.
[Illustration: FIG. 1.--Shell-bark Hickory (_Carya alba_) in flower.]
Most of the hickories form fine-looking noble trees of from 60 to 90 ft. in height, with straight, symmetrical trunks, well-balanced ample heads, and bold, handsome, pinnated foliage. When confined in the forest they shoot up 50 to 60 ft. without branches, but when standing alone they expand into a fine head, and produce a lofty round-headed pyramid of foliage. They have all the qualities necessary to constitute fine graceful park trees. The most ornamental of the species are _C. olivaeformis_, _C. alba_ and _C. porcina_, the last two also producing delicious nuts, and being worthy of cultivation for their fruit alone.