2l8 



The Walnuts 



2. THE BLACK WALNUT — Juglans nigra Linnaus 



This grand tree occurs in rich soil, particularly in the bottom lands of river 

 valleys from western Massachusetts to southern Ontario and Minnesota, south- 

 ward to Georgia, Florida, Mississippi, and 

 Texas, reaching a maximum height of 50 

 meters, with a trunk diameter of 2.5 m. It is 

 also called Walnut tree and Walnut. 



The trunk is tall and straight. The 

 branches are stout and ascendingor spreading, 

 forming a round-topped tree. The bark is 5 

 to 7 cm. thick, deeply furrowed into nar- 

 row blunt ridges, which split into thick, close 

 scales of a dark brown color; that of younger 

 stems is smooth, somewhat scaly, brown 

 outside, dark gray underneath the scales. 

 The twigs are stout, pithy, densely covered 

 with brownish hairs, gradually becoming 

 nearly smooth, dull light brown, and marked 

 by conspicuous yellowish lenticels and large 

 angular leaf scars. The terminal buds are 

 ovoid, slightly flattened, 8 mm. long, obliquely 

 rounded at the apex, and covered by ovate 

 hairy scales. The axillary buds are small and blunt. The leaves are 3 to 6 dm. 

 long, including the stout, hairy leaf-stalk. There are 13 to 23 leaflets; the 

 terminal leaflet is often wanting. The leaflets are ovate or ovate-lanceolate, sharply 

 or taper pointed, rounded or somewhat heart-shaped at the unequal base, sharply 

 small-toothed on the margin, sessile or nearly so, thin, bright green, smooth and 

 faintly shining above, paler and softly hairy beneath. The staminate catkins are 

 S to K) cm. long, their bracts somewhat triangular, usually brown-hairy; perianth 

 rounded, 6-lobed, the lobes irregularly orbicular, concave, hairy on the outer sur- 

 face; stamens 20 to 30 in several series; anthers nearly sessile, purplish. The pistil- 

 late flowers are in 2-to 5-flowered spikes, ovoid, 6 mm. long, gradually narrowed 

 upward; stigmas spreading, 12 to 18 mm. long, yellowish green tinged with red. 

 The fruit is solitary or rarely in pairs, globular to oblong or somewhat pear-shaped, 

 5 to 8 cm. in diameter, rounded at both ends, yellowish green and roughish, with 

 a rather thick husk; the nut is globose to ovoid, slightly flattened, sometimes 

 broader than long, 2-celled above, 4-celled below the middle, the surface sculp- 

 tured into thick, irregular ridges, dark brown; the wall is hard, about 5 mm. 

 thick with irregular cavities; the seed is light brown, grooved and concave on the 

 back, deeply lobed at each end. 



The wood is hard, strong, rather coarse-grained, dark brown and satiny; 



Fig. 177. — Black Walnut. 



