266 TREES IN WINTER 



BLACK WALNUT 



Juglans nigra L. 



HABIT — A large tree, 50-75 ft. hig-h with a trunk diameter of 2-5 ft., 

 reaching- a height of 150 ft. and a trunk diameter of 6-8 ft. in the Ohio 

 valley; trunk straight, tapering, giving off stout branches, those below 

 often nearly horizontal or declined, those above arising at a sharper 

 angle, spreading, forming an open, symmetrical, round-topped head. 



BARK — Thick, dark, rough, deeply furrowed into rounded ridges; 

 inner bark becoming yellow on exposure to air. 



TWIGS — Stout, densely gray-downy to smooth and reddish-buff; bitter 

 to taste and coloring saliva yellow when chewed. LENTICELS — small, 

 pale, raised dots, rather inconspicuous. PITH — buff, paler than that 

 of Butternut, chambered, the open chambers several times wider than 

 the intervening diaphragms. 



IiEAF-SCARS — Large, conspicuous, elevated, 3-lobed. inversely 

 triangular to heart-shaped, upper margin distinctly notched, enclosing 

 the axillary bud; no downy pad above leaf-scar. BUNDLE-SCARS — 

 dark, conspicuous in 3 U-shaped clusters. 



BUDS — Pale, silky downy; terminal buds ovate, generally under 10 

 mm. long and scarcely longer than broad, slightly flattened, obliquely 

 blunt-pointed; lateral buds smaller, their outer scales opening at apex 

 during winter, frequently a single superposed accessory bud above 

 axillary bud. BUDvSCALES — thick, outer scales of terminal bud gener- 

 ally not evidently lobed. 



FRUIT — Round-oval, 4-10 cm. in diameter, husk smooth not regularly 

 splitting. NUT — dark brown, round-oval, slightly flattened, sculptured 

 with interrupted, irregular, thick ridges; within 4-celled below the 

 middle, 2-celled above; seed sweet, edible, oily, soon becoming rancid. 



COMPARISONS — The Black Walnut is most closely related to the 

 Butternut which it resembles in its chambered pith and the general 

 twig appearance. The Butternut, however, has terminal buds longer 

 than broad, downy pads above leaf-scars, which are not notched as are 

 leaf-scars of the Black Walnut, and it further has elongated rather 

 than spherical nuts. The pith is dark brown while that of Black 

 Walnut is pale buff and the chambers are not much wider than the 

 diaphragms. In habit it is a lower, more spreading tree than the 

 Black Walnut and the light gray color especially of the flat ridges of 

 the bark is further characteristic. The points of dissimilarity to the 

 Bitternut are mentioned under this latter species. 



DISTRIBUTION — Rich woods, largely destroyed for its valuable tim- 

 ber and now scarce; occasionally cultivated as an ornamental tree in 

 the eastern United States. Massachusetts, south to Florida; west to 

 Minnesota, Kansas, Arkansas and Texas. 



IN NEW ENGLAND — Maine, New Hampshire and Vermont — not re- 

 ported native; Massachusetts — rare east of the Connecticut river, occa- 

 sional along the western part of the Connecticut valley to the New 

 York line; Connecticut — rare, roadsides and rocky hillsides in most 

 localities derived from planted trees; Norwich. East Hartford, Newing- 

 ton, Southington. Seymour and Southbury, Trumbull and Easton; prob- 

 ably native at North Canaan; Rhode Island — doubtfully native, Appon- 

 aug, and elsewhere. 



"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, and in boat and ship building. 



