The aborigines of the country used hickory nuts of different kinds as food, and in the region in which the pecan grows as a native tree, it was valued by them above all its relatives.

Penicaut found in his travels that the Indians stored large amounts of pecans for winter use. The scientific name of the pecan is appropriately derived from two Indian words, "powcohiccora" and "pacan."

In 1785, the pecan was described under the name Juglans Pecan, by Marshall in his Arboretum Americanum. In 1818, Thomas Nuttall, an English botanist, separated the hickories from the walnuts and butternuts, putting them under a new genus which he called Carya, naming the pecan Carya olivaeformis. Nuttall's classification was followed for many years until it was found that in the year previous to the publication of his work, 1817, C. S. Rafinesque, a French naturalist, had separated the hickories along the same lines as Nuttall and published them under the name Hicoria. In accordance with the laws of priority, Rafinesque's name, Hicoria, takes precedence over Carya.

The family JuglandaceÆ, embraces but two genera, Juglans and Hicoria, the former including the walnuts and butternuts, and the latter the pecan and other hickories. With the exception of the Shellbark hickory, Hicoria ovata Britton, and the Big shellbark, Hicoria laciniosa Sargent, the pecan is the only one of the genus worthy of cultivation.

Family. JuglandaceÆ Lindl. Nat. Syst. Ed. 2, 180. 1836. Trees with alternate pinnate leaves and monoecious bracted flowers. Staminate flowers in long, drooping catkins, provided with three or more stamens and occasionally with an irregular-lobed perianth adnate to the bractlet and a rudimentary ovary. Anthers erect, with short filaments, two-celled; dehiscent longitudinally. Pistillate flowers bracted with a three to five, normally four-lobed calyx and sometimes with petals. Ovule solitary, erect, styles two, stigmatic along the inner surface. Fruit a bony nut, incompletely two to four-celled. Seed large, two to four-lobed, cotyledons corrugated, oily, without endosperm.

Genus. Hicoria Raf. Med. Rep. (II) 5:352. 1808. Trees, with close or scaly bark, odd-pinnate leaves and serrate leaflets. Staminate flowers in slender drooping catkins, borne in groups of three, occasionally on the new shoots, but usually from buds just back of the terminal buds on last year's shoots, calyx naked, adherent to the bract, unequally two-third lobed or cleft; stamens with short filaments, three to ten in number. Pistillate flowers, two to eight, produced on a terminal peduncle, calyx four-parted, petals none, styles two to four, short, papillose. Fruit oblong, or obovoid, the husk separating into four parts; nut smooth or angled, bony, incompletely two to four-celled. Seed oily, sweet, edible or bitter and astringent. Natives of eastern North America and Mexico.

Species. H. Pecan (Marsh.) Britton. Bull. Torr. Club, 15:282. 1888. Pecan, Illinois nut, a large tree, 75 to 170 feet in height and a diameter reaching 6 feet, with rough-broken bark. Young twigs and leaves pubescent, later nearly or quite glabrous; leaflets seven to fifteen, falcate, oblong—lanceolate, sharp-pointed, serrate, green and bright above, lighter below; staminate catkins five to six inches long, sessile or nearly so, sometimes borne near the base on the young shoots but usually from the uppermost lateral buds on last year's shoots; pistillate flowers terminal on shoots of the current season's growth, produced singly or in clusters of two to nine; fruit oblong cylindrical; husk four-valved; nut 3/4 to 2-1/2 inches in greatest diameter, roundish, or cylindrical and pointed, two-celled at the base, partition thin, bitter, seed deliciously sweet. Found native on the moist bottom lands along streams from Indiana south to Kentucky and from Iowa south to Texas, principally along the Mississippi and its tributaries, the Colorado river in Texas, and along some of its tributaries into Mexico.

Pollination.

Since two kinds of flowers are produced on the pecan, one bearing the pistils, the other stamens, the pollen must be transferred from the latter to the former in order that pollination may take place. In many plants the pollen is transferred from one plant or flower to another by means of insects; but in the pecan there are no bright colors, no nectar, no scent to attract insects to carry pollen, but, instead, the wind is the carrying agent and it needs no attractions. Pollen is produced in large quantities, necessarily so, since much of it is wasted.

Unfavorable weather conditions at time of blooming may, however, interfere seriously with pollination. Heavy winds or wind-storms, and rains of several days duration, may prevent the necessary and desired distribution of the pollen, as a result of which no fruit is formed.

Sometimes the staminate blooms are destroyed by frost while the pistillate ones escape. It makes little difference which is destroyed, however, as in either case the result is the same—no fruit sets.

The staminate flowers push out from the lateral buds at the same time the new shoot develops from the terminal one. The pistillate blossom does not appear until the terminal shoot has grown six or eight inches, and in the meantime it is protected by the unfolded leaves. The staminate bloom, on the contrary, is exposed from the first, having no leaves to protect it. In consequence it is much more likely to be cut off by frost. Dr. Trelease refers to several observations on proterandry (maturing of the pollen before the stigmas of the pistils) in the pecan. This, together with the unprotected condition of the staminate blooms, we believe, accounts in a large measure for the non-setting of fruit on the northern boundaries of the pecan area.

The artificial or hand pollination of the pecan is an easy matter and offers an inviting field for those interested in plant breeding. Emasculation, or the removal of the stamens from the flowers necessary in breeding so many plants, is not necessary in the pecan. All that is needed is to cover the pistillate blossoms with a sack until they are matured. At this time the inner or stigmatic surfaces of the pistils will be exposed and ready for the pollen. The pollen, collected from adjoining trees in bloom or brought from a distance, can then be placed upon the stigmas and the sack replaced. When the fruit is set, the paper sack should be replaced by one of mosquito netting. Some careful work has already been done along this line, and it is hoped that many more will take up the work. Much yet remains to be desired, and varieties may be better adapted to different sections. The ideal, large, full-meated, thin-shelled, prolific and precocious variety of pecan has not yet been brought forward. It may be accidentally discovered; it may be produced and can be produced by systematic, painstaking work in breeding. It is hoped that the number of workers in this inviting field may be increased. Some may be deterred by the fact that it will take the seedlings so long to come into bearing. But scions may be taken from the seedlings raised from cross-bred nuts, top-worked on large trees, and fruit could be obtained in many cases in a period not exceeding five or six years from the seed. Those which would not produce fruit in six years in this way might perhaps as well be discarded.