JUGLANS SIEBOLDIANA, Siebold's Walnut
- Juglans Sieboldiana, Maximowicz, Mél. Biol. viii. 633 fig. (1872); Lavallée, Arbor. Segrezianum, p. 1, tab. I. et II. (1885); Garden, 1895, xlvii. 442.
- Juglans ailantifolia, Hort. Sieb. ex Lavallée, loc. cit.; and Carrière in Revue Horticole, 1878, p. 414, figs. 85 and 86.
A tree attaining 50 feet in height and 5 feet in girth.
Leaves with thirteen to fifteen leaflets, which are sub-opposite, oblong, acuminate at the apex, with base rounded and unequal, sub-sessile, the petiolule being less than ji, inch; serrations fine, shallow, and irregular, directed forwards, ciliate between the teeth; upper surface finely pubescent, with both single and tufted hairs; lower surface pale in colour, covered with numerous stellate hairs, denser close to the midrib on which there are glandular hairs; rachis with long brown glandular hairs and a few small glands near its base. Young shoots green, with long white glandular hairs and white sessile glands; lenticels at first white, becoming brown, conspicuous. Leaf-scars obcordate, three-lobed, deeply notched above, and with a transverse band of pubescence along the upper edge.
Flowers: staminate catkins very long, up to 12 inches, with bracts obtuse at the apex and very villous, scale five-lobed. Pistillate spikes, five to twenty flowered, the rachis and flowers covered with rufous tomentum.
Fruit in long racemes which are ten to twenty inches long; globose to ovateoblong, shortly acuminate at the apex, viscid and covered with stellate hairs. Nuts ovoid or globose, rounded at the base and acuminate at the apex, with thick winglike sutures, very slightly wrinkled and pitted, not ribbed, rather thick-shelled.
Identification
This species seems to be practically identical in leaves and shoots with Juglans mandshurica, and differs little in these respects from Juglans cordiformis, except that the leaflets of the latter are distinctly cordate at the base. All three species differ, however, remarkably in fruit, and must be kept distinct on that account. They belong to the section of walnuts with bearded leaf-scars, and are readily distinguished from Juglans cinerea, the other species of this group, by having the leaf-scars deeply notched above.
In winter the following characters are available:—Twigs stout, brown, glabrous except near the tip, where the pubescence of summer is retained. Leaf-scars large, on very slightly raised pulvini, obovate, two-lobed above; upper margin convex, with a central notch, and surmounted by a raised band of pubescence; bundle-dots in three groups. Terminal bud brownish, elongated, covered with a dense minute pubescence; outer pair of scales lobed at the apex. Lateral buds arising at an
