1. JUGLANS L. Walnut.
Trees, with furrowed scaly bark, durable dark-colored wood, stout branchlets, laminate pith, terminal buds with 2 pairs of opposite more or less open scales often obscurely pinnate at apex, those of the inner pair more or less leaf-like, and obtuse slightly flattened axillary buds formed before midsummer and covered with 4 ovate rounded scales, closed or open during winter. Leaves with numerous leaflets, and terete petioles leaving in falling large conspicuous elevated obcordate 3-lobed leaf-scars displaying 3 equidistant U-shaped clusters of dark fibro-vascular bundle-scars; leaflets conduplicate in the bud, ovate, acute or acuminate, mostly unequal at base, with veins arcuate and united near the margins. Aments of the staminate flowers many-flowered, elongated, solitary or in pairs from lower axillary buds of upper nodes, appearing from between persistent bud-scales in the autumn and remaining during the winter as short cones covered by the closely imbricated bracts of the flowers; calyx 3—6-lobed, its bract free only at the apex; stamens 8—40, in 2 or several ranks, their anthers surmounted by a conspicuous dilated truncate or lobed connective; pistillate flowers in few-flowered spikes, their involucre villose, free only at the apex and variously cut into a laciniate border (corolla?) shorter than the erect calyx-lobes; ovary rarely of 3 carpels; stigmas club-shaped, elongated, fimbriately plumose. Fruit ovoid, globose or pyriform, round or obscurely 4-angled, with a fleshy indehiscent glabrate or hirsute husk; nut ovoid or globose, more or less flattened, hard, thick-walled, longitudinally and irregularly rugose, the valves alternate with the cotyledons, and more or less ribbed along the dorsal sutures and in some species also on the marginal sutures. Seed more or less compressed, gradually narrowed or broad and deeply lobed at base, with conspicuous dark veins radiating from the apex and from the minute basal hilum.
Juglans is confined to temperate North America, the West Indies, South America from Venezuela to Peru, western and northern China, Korea, Manchuria, Japan, and Formosa. Eleven species are known. Of exotic species Juglans regia L., an inhabitant probably originally of China, is cultivated in the middle Atlantic and southern states and largely in California for its edible nuts, which are an important article of commerce. The wood of several species is valued for the interior finish of houses and for furniture.
Juglans, from Jupiter and glands, is the classical name of the Walnut-tree.
CONSPECTUS OF THE NORTH AMERICAN SPECIES.
Fruit racemose; nut 4-ribbed at the sutures with smaller intermediate ribs, 2-celled at the base; heartwood light brown; leaflets 11—17, oblong-lanceolate.1. [J. cinerea] (A, C). Fruit usually solitary or in pairs; nut without sutural ribs, 4-celled at the base; heartwood dark brown. Nuts prominently and irregularly ridged with often interrupted ridges; leaflets 15—23, ovate-lanceolate.2. [J. nigra] (A, C). Nuts more or less deeply longitudinally grooved. Nuts up to 1½′ in diameter; leaflets 9—13, rarely 19, oblong-lanceolate to ovate, acuminate, coarsely serrate.3. [J. major] (F, H). Nuts not more than ¾′ in diameter. Leaflets 17—23, narrow-lanceolate, long-pointed.4. [J. rupestris] (C). Leaflets 11—15 or rarely 19, oblong-lanceolate, acute or acuminate, the lower often rounded at the apex.5. [J. californica] (G). Nuts obscurely or not at all grooved, up to 2′ in diameter; leaflets 15—19, ovate-lanceolate to lanceolate, long-pointed.6. [J. Hindsii] (G).
1. [Juglans cinerea] L. Butternut.
Leaves 15′—30′ long, with stout pubescent petioles, and 11—17 oblong-lanceolate acute or acuminate leaflets 2′—3′ long, 1½′—2′ wide, finely serrate except at the unequal rounded base, glandular and sticky as they unfold, at maturity thin, yellow-green and rugose above, pale and soft-pubescent below; turning yellow or brown and falling early in the autumn. Flowers: staminate in thick aments 3′—5′ long; calyx usually 6-lobed, light yellow-green, puberulous on the outer surface, ¼′ long, its bract rusty-pubescent, acute at apex; stamens 8—12, with nearly sessile dark brown anthers and slightly lobed connectives; pistillate in 6—8-flowered spikes, constricted above the middle, about ⅓′ long, its bract and bractlets coated with sticky white or pink glandular hairs and rather shorter than the linear-lanceolate calyx-lobes; stigmas bright red, ½′ long. Fruit in 3—5 fruited drooping clusters, obscurely 2 or rarely 4-ridged, ovoid-oblong, coated with rusty clammy matted hairs, 1½′—2½′ long with a thick husk; nut ovoid, abruptly contracted and acuminate at apex, with 4 prominent and 4 narrow less conspicuous ribs, light brown, deeply sculptured between the ribs into thin broad irregular longitudinal plates, 2-celled at the base and 1-celled above the middle; seed sweet, very oily, soon becoming rancid.
A tree, occasionally 100° high, with a tall straight trunk 2°—3° in diameter, and sometimes free of branches for half its height; more frequently divided 20° or 30° above the ground into many stout limbs spreading horizontally and forming a broad low symmetrical round-topped head, and dark orange-brown or bright green rather lustrous branchlets coated at first with rufous pubescence, covered more or less thickly with pale lenticels, gradually becoming puberulous, brown tinged with red or orange in their second year and marked by light gray leaf-scars with large black fibro-vascular bundle-scars and elevated bands of pale tomentum separating them from the lowest axillary bud. Winter-buds: terminal ½′—⅔′ long, ¼′ wide, flattened and obliquely truncate at apex, their outer scales coated with short pale pubescence; axillary buds ovoid, flattened, rounded at apex, ⅛′ long, covered with rusty brown or pale pubescence. Bark of young stems and of the branches smooth and light gray, becoming on old trees ¾′—1′ thick, light brown, deeply divided into broad ridges separating on the surface into small appressed plate-like scales. Wood light, soft, not strong, coarse-grained, light brown, turning darker with exposure, with thin light-colored sapwood composed of 5 or 6 layers of annual growth; largely employed in the interior finish of houses, and for furniture. The inner bark possesses mild cathartic properties. Sugar is made from the sap, and the green husks of the fruit are used to dye cloth yellow or orange color.
Distribution. Rich moist soil near the banks of streams and on low rocky hills, southern New Brunswick to the valley of the St. Lawrence River in Ontario, the northern peninsular of Michigan, southern Minnesota, eastern South Dakota, eastern Iowa, southeastern Nebraska, and southward to central Kansas, northern Arkansas, Delaware, eastern Virginia, and on the Appalachian Mountains and their foothills to northern Georgia; in northern Alabama, southern Illinois and western Tennessee; most abundant northward.
Occasionally cultivated.
× Juglans quadrangulata A. Rehd., a natural hybrid of J. cinerea and the so-called English Walnut (J. regia) is not uncommon in eastern Massachusetts, and a hybrid of J. cinerea with the Japanese J. Sieboldiana Maxm. has appeared in the United States.
2. [Juglans nigra] L. Black Walnut.
Leaves 1°—2° long, with pubescent petioles, and 15—23 ovate-lanceolate leaflets 3′—3½′ long, 1′—1¼′ wide, long-pointed, sharply serrate except at the more or less rounded often unequal base, thin, bright yellow-green, lustrous and glabrous above, soft-pubescent below, especially along the slender midrib and primary veins; turning bright clear yellow in the autumn before falling. Flowers: staminate in stout puberulous aments 3′—5′ long, calyx rotund, 6-lobed, with nearly orbicular lobes concave and pubescent on the outer surface, its bract ¼′ long, nearly triangular, coated with rusty brown or pale tomentum; stamens 20—30, arranged in many series, with nearly sessile purple and truncate connectives; pistillate in 2—5 flowered spikes, ovoid, gradually narrowed at the apex, ¼′ long, their bract and bractlets coated below with pale glandular hairs and green and puberulous above, sometimes irregularly cut into a laciniate border, or reduced to an obscure ring just below the apex of the ovary; calyx-lobes ovate, acute, light green, puberulous on the outer, glabrous or pilose on the inner surface; stigmas yellow-green tinged on the margins with red, ½′—¾′ long. Fruit solitary or in pairs, globose, oblong and pointed at apex, or slightly pyriform, light yellow-green, roughened by clusters of short pale articulate hairs, 1½′—2′ in diameter, with a thick husk; nut oval or oblong, slightly flattened, 1⅛′—1½′ in diameter, dark brown tinged with red, deeply divided on the outer surface into thin or thick often interrupted irregular ridges, 4-celled at base and slightly 2-celled at the apex; seed sweet, soon becoming rancid.
A tree, frequently 100° and occasionally 150° high, with a straight trunk often clear of branches for 50°—60° and 4°—6° in diameter, thick limbs spreading gradually and forming a comparatively narrow shapely round-topped head of mostly upright rigid branches, and stout branchlets covered at first with pale or rusty matted hairs, dull orange-brown and pilose or puberulous during their first winter, marked by raised conspicuous orange-colored lenticels and elevated pale leaf-scars, gradually growing darker and ultimately light brown. Winter-buds: terminal ovoid, slightly flattened, obliquely rounded at apex, coated with pale silky tomentum, ⅓′ long, with usually 4 obscurely pinnate scales; axillary ⅛′ long, tomentose, their outer scales opening at the apex during the winter. Bark of young stems and branches light brown and covered with thin scales, becoming on old trees 2′—3′ thick, dark brown slightly tinged with red, and deeply divided into broad rounded ridges broken on the surface into thick appressed scales. Wood heavy, hard, strong, rather coarse-grained, very durable, rich dark brown, with thin lighter colored sapwood of 10—20 layers of annual growth; largely used in cabinet-making, the interior finish of houses, gun-stocks, air-planes, and in boat and shipbuilding.
Distribution. Rich bottom-lands and fertile hillsides, western Massachusetts to southern Ontario, southern Michigan, southeastern Minnesota, central and northern Nebraska, central Kansas, eastern Oklahoma, and southward to western Florida, central Alabama and Mississippi, and the valley of the San Antonio River, Texas; most abundant in the region west of the Alleghany Mountains, and of its largest size on the western slopes of the high mountains of North Carolina and Tennessee, and on the fertile river bottom-lands of southern Illinois and Indiana, southwestern Arkansas, and Oklahoma; largely destroyed for its valuable timber, and now rare.
Occasionally cultivated as an ornamental tree in the eastern United States, and in western and central Europe. × Juglans intermedia Carr., a natural hybrid, of J. nigra with the so-called English Walnut (J. regia) has appeared in the United States and Europe, and on the banks of the James River in Virginia has grown to a larger size than any other recorded Walnut-tree. In California a hybrid, known as “Royal,” between J. nigra and J. Hindsii has been artificially produced.
3. [Juglans major] Hell. Nogal.
Juglans rupestris var. major Torr.
Juglans rupestris Sarg., in part, not Engelm.
Leaves 8′—12′ long, with slender pubescent petioles and rachis, and 9—13 rarely 19 oblong-lanceolate to ovate acuminate often slightly falcate coarsely serrate leaflets cuneate or rounded at base, coated when they first appear with scurfy pubescence, soon becoming glabrous, or at maturity slightly pubescent on the midrib below, 3′—4′, or those of the lower pairs 1½′—2′ long, and 1′—1½′ wide, thin, yellow-green, with a thin conspicuous yellow midrib and primary veins. Flowers: staminate in slender puberulous or pubescent aments 8′—10′ long; calyx nearly orbicular, long-stalked, pale yellow-green, 5 or 6-lobed, the lobes ovate, acute, hoary pubescent on the outer surface, their bract acute, coated with thick pale tomentum; stamens 30—40, with nearly sessile yellow anthers, and slightly divided connectives; pistillate not seen. Fruit subglobose to slightly ovoid or oblong, abruptly contracted at apex into a short point (J. elæopyren Dode), densely tomentose when half grown, 1′—1½′ in diameter, with a thin husk covered with close rufous pubescence; nut dark brown or black, slightly compressed, usually rather broader than high, or ovoid, rounded or bluntly acute at apex, rounded and sometimes depressed at base, longitudinally grooved with broad deep grooves, thick shelled; seed small and sweet.
A tree sometimes 50° high, with a straight trunk occasionally 3°—4° in diameter, or divided at the ground into several large stems, stout branches forming a narrow head, and slender branchlets thickly coated when they first appear with rufous pubescence, becoming red-brown, pubescent or puberulous and marked by many small pale lenticels at the end of their first season and ashy gray the following year.
Distribution. Banks of streams in the cañons of central and southern New Mexico and Arizona, and on Oak Creek near Flagstaff, Arizona on the Colorado plateau (P. Lowell).
4. [Juglans rupestris] Engelm. Walnut.
Leaves 9′—12′ long, with slender pubescent or puberulous petioles and rachis, and 13—23 narrow lanceolate long-pointed usually falcate finely serrate leaflets entire or nearly entire on their incurved margins, cuneate or rounded at base, thin, light green, glabrous or pubescent on the midrib below, 2′—3′ long and ⅓′—⅔′ wide. Flowers: staminate in slender aments, 3′—4′ long, pubescent when they first appear, becoming glabrous; calyx short-stalked, nearly orbicular, light yellow-green, puberulous on the outer surface, 3—5-lobed with rounded lobes, their bracts ovate-lanceolate, coated with hoary tomentum; stamens about 20, with nearly sessile yellow anthers and slightly lobed connectives; pistillate flowers oblong, narrowed at the ends, thickly coated with rufous pubescence; bract and bractlets irregularly divided into a laciniate border rather shorter than the ovate acute calyx-lobes; stigmas green tinged with red, ⅓′ long. Fruit globose or subglobose, tipped with the persistent remnants of the calyx, pubescent or puberulous with rusty hairs, ½′—¾′ in diameter, with a thin husk; nut subglobose to slightly ovoid, sometimes obscurely 4-ridged from the apex nearly to the middle (J. subrupestris Dode), deeply grooved with longitudinal simple or forked grooves, 4-celled at base, 2-celled at apex, thick shelled; seed small and sweet.
A shrubby round-headed tree occasionally 20°—30° high, with a short generally leaning trunk 18′—30′ in diameter, usually branching from near the ground, and slender branchlets coated with pale scurfy pubescence often persistent for two or three years, orange-red and marked by pale lenticels in their first winter and ultimately ashy gray; often a shrub with clustered stems only a few feet high. Winter-buds: terminal, ¼′—½′ long, compressed, narrowed and often oblique at apex, covered with pale tomentum; axillary ⅛′ long, compressed, coated with pale pubescence. Wood heavy, hard, not strong, rich dark brown with thick white sapwood. The beauty of the veneers obtained from the stumps of the large trees is fast causing their destruction.
Distribution. Limestone banks of the streams of southern, central and western Texas from the Rio Grande to the mountains in the western part of the state; western Oklahoma (Kiowa, Greer, Beckham, Rogel, Mills and Ellis Counties); southeastern New Mexico.
Occasionally cultivated in the eastern United States and in Europe, and hardy as far north as eastern Massachusetts; interesting as producing the smallest nuts of any of the known Walnut-trees.
5. [Juglans californica] S. Wats.
Leaves 6′—9′ long, with glandular pubescent petioles and rachis, and 11—15, rarely 19, oblong-lanceolate acute or acuminate glabrous finely serrate leaflets cuneate or rounded at base, 1′—2½′ long and ⅓′—¾′ wide, the lower often rounded at apex. Flowers: staminate in slender glabrous or puberulous aments 2′—3′ long; calyx puberulous on the outer surface with acute or rarely rounded lobes, its bract, puberulous; stamens 30—40, with yellow anthers and short connectives bifid at apex; the pistillate subglobose, puberulous; stigmas yellow, ½′ long. Fruit globose, ⅓′—¾′ in diameter, with a thin dark-colored puberulous husk; nut nearly globose, deeply grooved with longitudinal grooves, thick shelled, 4-celled at base, imperfectly 2-celled at apex; seed small and sweet.
A shrubby round-headed tree or shrub generally 12°—20°, rarely 40°—50° high, usually branching from the ground or with a short trunk 1° or rarely 2°—3° in diameter, and slender branchlets coated with scurfy rufous pubescence when they first appear, glabrous, reddish brown and marked by pale lenticels at the end of their first season and gray the following year. Winter-buds coated with rufous tomentum.
Distribution. Banks of streams and bottom-lands in the southern California coast region from Santa Barbara and the Ojai valley to San Fernando and the Sierra Santa Monica, and along the foothills of the Sierra Madre to the San Bernardino Mountains and southward to the Sierra Santa Anna.
A curious seminal variety (var. quercina Babcock) with compound leaves composed of 3 oval leaflets, the terminal long-stalked and 2 or 3 times larger than the lateral leaflets, is occasionally cultivated in California.
6. [Juglans Hindsii] Rehd.
Juglans californica S. Wats., in part.
Juglans californica var. Hindsii Jep.
Leaves 9′—12′ long, with slender villose pubescent petioles and rachis, and 15—19, usually 19, ovate-lanceolate to lanceolate long-pointed often slightly falcate leaflets, serrate with remote teeth except toward the usually rounded cuneate or rarely cordate base, thin, puberulous above while young, becoming bright green, lustrous and glabrous on the upper surface, below furnished with conspicuous tufts of pale hairs, and villose-pubescent along the midrib and primary veins, 2½′—4′ long and ¾′—1′ wide. Flowers: staminate in slender glabrous or sparingly villose aments 3′—5′ long; calyx elongated, coated like its bract with scurfy pubescence, divided into 5 or 6 acute lobes; stamens 30—40, with short connectives bifid at apex; ovary of the pistillate flower oblong-ovoid, thickly covered with villose pubescence, ⅛′ long, the border of the thin bract and bractlets much shorter than the calyx-lobes; stigma yellow. Fruit globose, 1¼′—2′ in diameter, with a thin dark-colored husk covered with short soft pubescence; nut nearly globose, somewhat flattened at the ends, faintly grooved with remote longitudinal depressions, thick shelled; seed small and sweet.
A tree usually 30°—40°, occasionally 75° high, with a tall trunk 1°—2° in diameter, stout pendulous branches forming a narrow round-topped head, and comparatively slender branchlets thickly coated when they first appear with villose pubescence, reddish brown and puberulous, and marked by pale lenticels and small elevated obscurely 3-lobed leaf scars during their first winter, becoming darker and nearly glabrous in their second year. Winter-buds coated with hoary tomentum; terminal acute, compressed, more or less enlarged at apex, ¼′—⅓′ long; axillary usually solitary, nearly globose, about 1/16′ in diameter. Bark gray-brown, smoothish, longitudinally fissured into narrow plates. Wood heavy, hard, rather coarse-grained, dark brown often mottled, with thick pale sapwood of from 8 to 10 layers of annual growth.
Distribution. Coast region of central California; banks of the lower Sacramento River; along streams near the western base of Mt. Diablo, and on eastern slope of the Napa Range near Atlas Peak east of Napa Valley; near Loyalton in the Sierra Valley.
Often cultivated in California as a shade tree and as stock on which to graft varieties of Juglans regia L., and rarely in the eastern states and in Europe. In California, a hybrid known as “Paradox” between J. Hindsii and J. regia has been artificially produced.