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air and attacks of insect-eating birds. These trees appeared to have been infested for several years, as there was scarcely a spot on the surface of the wood that had not been scarified with this pest. Since the destruction of these trees I have not been troubled with bark borers, although there are still a number of very old and large hickories thriving in the same grove. The only remedy I can suggest is to cut down infested trees as soon as they are discovered, and also encourage the insect-eating birds to remain in and near the nut groves.

There are several other species of bark borers that occasionally attack hickories, one of these, the Chramesus icoriæ, Leconte, infests the small twigs, while another, the Sinoxylon basilare, Say, after boring through the bark, continues its course far into the heartwood, showing a preference for this kind of food instead of the living tissues. These pests, however, are rarely constant, but very erratic, in their attacks, and while they may be rather abundant on a few or many trees a season or two, they then disappear, and not one may be seen for several decades.

THE HICKORY-SHUCK WORM (Grapholitha caryana. Fitch). The parent of this pest is a minute moth of the family Tortricidæ, the small caterpillars mining and boring the green husks, and sometimes into the immature shell, causing the nuts to wither and drop off prematurely, although an occasional one may reach maturity, even in its scarified condition. This insect appears to be somewhat rare in the East, but very abundant some years in the West, where it is frequently destructive to the thick shellbark hickory and pecan. The first fresh specimens of the Nussbaumer Hybrid pecan nut (referred to on a preceding page) were so badly bored and scarified by this worm when received, that they would have been nearly or quite worthless for either planting or other purposes. As this insect attacks the

nuts on the very largest trees in the forest and elsewhere, I cannot suggest any other remedy than to gather the immature and infested nuts as they fall, and burn them, with their contents.

Among the larger Lepidoptera (butterflies and moths) there are many species, the caterpillars of which occasionally feed on the leaves of the hickories, but not exclusively; consequently, they cannot be considered as the special enemies of this genus of trees. When they do attack them, it is as much due to accident as design. This is certainly true with the great Luna moth (Attacus luna) and the American silk worm (Telea polyphemus), and various species of the Catocala, as well as the Tent caterpillar (Clisiocampa sylvatica).

There is also a hickory-nut weevil, closely allied to the species infesting the chestnut; and while not quite as large, its habits are similar, and its ravages may be checked by the same or similar means. The grubs bore into the green nuts, causing some to fall before halfgrown; others may remain in the nuts until they are ripe and gathered in the autumn; consequently, perforated hickory nuts are not at all rare, even on the stands of venders in our cities.

Bud worms, leaf miners, leaf rollers and plant lice, -and among the latter several gall-making species,—are to be found on the hickories; but with all these natural enemies to contend with, the hickories thrive, grow, and yield their fruits in greater or less abundance. To enumerate, describe and illustrate all the insects known to be enemies of the hickory would require a large volume, but fortunately there are many special works published on the insects injurious to vegetation, and these are readily obtainable by all who may have occasion to consult their pages.

CHAPTER VIII.

THE WALNUT.

Juglans. The ancient Latin name, first used by Pliny, contracted from Jovis glans, the nut of Jove or Jupiter. A genus of about eight species, three or four of these indigenous to the United States.

Order, Juglandacea (Walnut family).-Medium to large deciduous trees with odd-pinnate leaves; leaflets from fifteen to twenty-one, serrate, mainly oblong and pointed. The sexes of flowers separate (monoecious) on the same tree, the males in pendulous green cylindrical catkins two to three inches long, solitary or in pairs, sessile,-not stalked, as in the hickories,-issuing from the one-year-old twigs, and at the upper edge of the scar left by the falling leaf of the previous season (Fig. 73), showing that the male organs emanate from an aggregation of bud-cells in the axils of the leaves during the preceding summer and autumn. Female flowers terminal on the new growth in spring, also single, in clusters, and occasionally in long pendulous racemes with a four-cleft calyx, four minute petals and two thick curved stigmas. Fruit round or oblong (Fig. 74); husk thin, drying up without opening by seams, as in the hickories. Shell of nut either rough and deeply corrugated, with sharp-pointed ridges, or quite smooth, with an undulating, wavy surface, very thick in some species and thin in others; kernel two- or indistinctly four-lobed, united at the apex, fleshy, rich and oily.

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History. The common walnut, so long and widely known in commerce under various names, such

as Persian, English, French, Italian and European wal nuts, also as Madeira nut, and recently Chile walnut, are now all believed to have descended from trees native of Persia, most plentiful in the province of Ghilan on the Caspian sea, between latitude 35° and 40°, hence the

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FIG. 73. PERSIAN WALNUT, SHOWING POSITION OF SEXUAL ORGANS.

old Grecian name of the fruit, viz.: Persicon and Basilicon, or Persian Royal nut, probably because either introduced by the Greek monarchs, or sent to them by the Persian kings. Later,-according to Pliny,-the Greeks called the trees Caryon, on account of the strong

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