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.