Trees of New York State 179 



FAGACEAE 



Quercus inacrocarpa Miclix. 



Bur Oak, Mossy-cup Oak, Over-cup Oak 



Habit — One of the largest of Auieriean oaks, under optimum conditiona 

 sometimes 170 feet in height with a trunk 4-7 feet in diameter which is 

 free of branches for 50 feet or more. Usually smaller, becoming shrubby 

 at the northern limits of its range. Crowii in the open broad and round- 

 topped, witli massive, spreading limbs and drooping, bushy brauchlets. 



Leaves — Alternate, obovate or oblong, G-12 inches long, 3-6 inches wide, 

 cuneate at the base, sinuately cut or nearly divided into 5-7 lobes, the 

 terminal lobe the larger and erenately lobed. At maturity leaves thick, 

 firm, lustrous and usually smooth above, greenish or silverj- pubescent 

 below. Petioles stout, %-l inch long. 



Flowers — In our range appearing in late May or early June when the 

 leaves are about one-fourth grown, monoecious. Staminate flowers in 

 interrupted, hairy, filiform, pendulous, deciduous aments, 4-6 inches long 

 which are borne on the growth of the preceding season or from the axils 

 of the inner scales of the terminal bud. Calyx hemi-spherical, yellowish 

 green, pubescent wdth 4-6 laciniate lobes. Stamens 4r-6, wdth short fila- 

 ments and yellow, glabrous anthers. Pistillate flowers sessile or pedun- 

 culate, solitary or paired, borne in the axils of the leaves of the season, 

 each subtended by broadly ovate, pubescent involucral scales. Calyx 

 campanulate, shallowly lobed, adnate to the ovary. Pistil enclosed aside 

 from the 3 spreading styles which are reddish and stigma tic on their 

 inner surface. 



Fruit — ■ A sessile or short-pedunculate acorn ripening the first season. Nut 

 chestuut-bro\\ii, oval or broadly ovate, rounded and finely pubescent at 

 the apex, from •%-2 inches long, enclosed from one-half to its whole 

 length in the cup. Cup bowl-shaped, pale brown and pubescent within, 

 hoar)--tomeutose without, A\'ith pointed, imbricated scales, the upper pro- 

 longed to form a fringe. 



Winter characters — Twigs stout, pale-lentieellate, glabrous, pale orange- 

 yellow, at length dark bro^^^l. Older t\\-igs often develop corky wings. 

 Buds alternate, those near the branch-tip clustered about the terminal 

 bud, broadly ovate, obtuse, pubescent, pale reddish brown, Vs-V-t of an 

 inch long. Mature bark pale brown, medium thick, divided by deep fur- 

 rows into irregular, scaly plates. 



Habitat — A bottom-land species preferring rich, deep, moist soils, more 

 rarely on drier, upland sites. 



Range — Nova Scotia to Manitoba and Montana, south to Pennsylvania. Ten- 

 nessee and Texas. Zones A, B, and C. 



Uses — A valuable timber species producing lumber equivalent in quality to 

 that of White Oak. Wood hard, heavy, strong, durable, rich brown ■^^■ith 

 paler sapwood. Prized for furniture, cooperage, interior finish, railroad 

 ties, etc. 



