302 TREES IN" WINTER 



BUR OAK 

 Mossy-cup or Over-cup Oak. 



Quercus macrocarpa Michx. 



HABIT — Although one of our largest Oaks in the central states, in 

 New England of medium size only 40-60 ft. in height with a trunk 

 diameter of 1-3 ft.; in the open forming a broad, round top with thick 

 spreading limbs and numerous often drooping branchlets. 



BARK — Flaky, resembling that of White Oak but rather darker and 

 with ridges rather firmer. 



TWIGS — Stout, yellowish-brown, smooth or downy, twigs on some 

 trees after the first year developing corky ridges. LENTICELS — minute, 

 pale, raised dots, inconspicuous. LEAVES — which sometimes persist, 

 obovate-oblong, divided by deep indentations into 5-7 rounded lobes, the 

 terminal lobe the largest. PITH — 5-pointed, star-shaped. 



BUDS — Conical to broadly ovate, sharp-pointed or blunt, 3-5 mm. 

 long, reddish-brown, covered with pale wool; lateral buds more or 

 less strongly appressed and flattened against the twig. Stipules often 

 persisting at tips of twigs, long, downy thread-like. BUD-SCALES — 



relatively few to a bud. 



FRUIT— Maturing in autumn of first year, very variable, sessile or 

 stalked, generally single. NUT — ovate to oval, 2-5 cm. long, apex 

 rounded or depressed, covered with pale down. CUP — thick, hemi- 

 spherical to top-shaped enclosing from % to the entire nut; scales of 

 cup, pale, woolly, thickened at base with pointed tips, tips of upper 

 scales prolonged into a more or less distinct fringe. 



COMPARISONS — The Bur Oak is sharply distinguished from our 

 other Oaks by a number of well-marked characters such as the presence 

 of corky ridges on the young branchlets, the copious fringe to the 

 large acorn, the appressed and downy buds. These characters, however, 

 are not always present in a given specimen; thus the coiky ridges 

 may fail to appear throughout an entire tree; the acorns may be 

 reduced in size and in the distinctness of the fiinge; and the lateral 

 buds may be more or less divergent. 



DISTRIBUTIOiV — Low rich bottom lands. Nova Scotia to Manitoba; 

 south to Pennsylvania and Tennessee; west to Montana, Nebraska, 

 Kansas, Oklahoma and Texas. 



IN NEW ENGLAND — Maine — known only in the valleys of the middle 

 Penobscot and the Kennebec; Vermont — lowlands, about Lake Cham- 

 plain, especially in Addison county, not common; Massachusetts — valley 

 of the Ware river, Stockbridge and towns south along the Housatonic 

 river; Connecticut — rich bottom lands or swampy places, rare or local 

 and confined to the northwestern part of the state; reported from Ca- 

 naan and Salisbury; Rhode Island — no station reported. 



WOOD — Similar to that of White Oak from which it is not generally 

 distinguished commercially, although superior in strength. 



