126 



SILVA OF NORTH AMERICA. 



JUGLANDACE^. 



grown, is three to five-lobed, nearly orbicular, light yellow-green, glabrous, or slightly pubescent on the 



lower surface, and raised 



abo 



slender stalt, which is about a quarter of an inch long. There 



twenty stamens, with nearly sessile yellow anthers and dark conspicuous sKghtly lobed con- 

 nectives. The pistillate flowers, which are produced in few-flowered spikes, are narrowed at both ends, 

 coated with pale or rufous tomentum, and from one eighth to one quarter of an inch in length; the 

 bract and bractlets are green above, puberulous at the apex on the outer surface, and irregularly divided 



is on the 



laciniately cut border rather shorter than the ovate-acute sepals, Avhich are puberulo 



surface 



The stigmas are club-shaped, spreading, green tinged with red, and one third of 



inch long. The fruit is globose or rarely oblong, and varies from half an inch to an inch and a half 

 diameter, with a thin husk, glabrate or coated with short rufous articulate hairs. The nut is globe 



without sutural ridges, often compressed at both ends and sometimes flattened 



ally, dark reddish 



brown to black, and deeply sulcate with longitudinal simple or forked grooves ; it is four-celled at the 

 base and two-celled at the apex, with very thick hard walls, containing numerous interior 



inclosing a small sweet kernel. The cotyledons are keeled on the back, flat or slightly 



cavities, and 

 cave on the 



inner face, more or less deeply lobed below and above, and abruptly contracted into the short pointed 

 radicle.^ 



Jiiglans rui^estris is distributed from the valleys of the upper Colorado, the Llano, and Guada- 

 loupe Rivers in central Texas, westward through southern New Mexico and Arizona, and southward 

 into the states of northern Mexico. In Texas, where it is common west of the ninety-eighth meridian 

 on streams flowing to the Gulf of Mexico, Jiiglans rupestvis is often shrubby, and is rarely more than 

 thirty feet in height, growing on the limestone banks of streams or sometimes in their stony beds with 

 the narrow-leaved Chestnut Oak, the Plane-tree, the Green Ash, the Cedar Elm, the Red Mulberry, and 

 the black-fruited Persimmon ; in New Mexico and Arizona, where it attains its largest size, it is a 

 common inhabitant of canons in all the mountain ranges south of the Colorado plateau, growing from 

 their mouths up to elevations of six thousand feet, with Cottonwoods, the Black Willow, the Alder, and 



Plane-tree, alway 



the banks of the streams 



where the roots, penetrating 



deep into the soil, are able to secure a constant supply of water. 



The wood of Jiiglans Tiipestris is heavy, hard, not very strong, and coarse-grained, with a satiny 

 surface susceptible of receiving a good pohsh ; it contains numerous irregularly distributed large open 

 ducts and thin obscure medullary rays. It is rich dark brown, with thick nearly white sapwood. The 

 specific gravity of the absolutely dry wood of the New Mexico and Arizona trees is 0.6861, a cubic foot 

 weighing 42.14: pounds. 



In New Mexico and Arizona the nuts are gathered and eaten by Mexicans and Indians. The 

 kernel is very sweet and remains fresh for a long time, but its commercial value is lessened by its small 

 size and the thickness and hardness of the walls which inclose it. 



Juglans rimestris was discovered in western Texas in 1835^ by the Belgian botanist Berlandier;^ 



in 1868 it was growing in the Botanic Garden at Berlin ; ^ and in 1879 it was introduced into the 



Texas. It is perfectly hardy in eastern 



Arnold Arboretum by means of seeds gathered in western 

 Massachusetts, where as a low shrub it has ripened fruit. 



In the canons of the Arizona mountains Juglans rupestris is a handsome and conspicuous tree, 

 particularly in winter, when its head of rigid white branches makes it peculiarly effective. 



^ The eastern and westeru forms of Juglans rupestris seem some- cccxxxvi., the var. major of Torrey) is a larger tree, with broader 



times like distinct species; but in the extreme western part of and more coarsely serrate stalked leaflets, usually pubescent on the 



Texas and in New Mexico the two forms grow together and appear lower surface, larger fruit coated with rufous hairs, and a darker, 



to pass one into the other. The Texas form (Plate cccxxxv.) is dis- more flattened, and more deeply sulcate nut with proportionately 



tingnished by its smaller size, by its narrower, more glabrous, and thinner walls and a larger kernel. 



more finely serrate leaflets, which are often nearly sessile, and by 

 the small globose glabrate fruit and very thick-walled nut inclosing 

 a kernel often scarcely larger than a pea. The western form (Plate 



2 No. 2459, " Rio de Medina, Texas, June, 1834.'* 



8 See i. 82. 



* Teste, Herb. Engelmann. 



