1304 The Trees of Great Britain and Ireland 



south to Florida, and westward through the Gulf States to Trinity river, Texas, 

 ascending the Mississippi basin to southern Indiana and Illinois, most common and 

 attaining its largest size in Louisiana. 



The overcup oak was introduced ^ by Fraser in 1786, but Loudon only mentions 

 in 1838 a small plant in Loddiges' nursery. Probably neglected by nurserymen, 

 and unsuited for our climate, it is now neariy unknown in cultivation, the only 

 specimens which we have seen being two trees in Kew Gardens, about 10 ft. high, 

 which were obtained from the Arnold Arboretum in 1897. (A. H.) 



QUERCUS MACROCARPA, Burr Oak 



Quercus macrocarpa, Michaux, Hist. Chines Am. No. 2, tt. 2, 3 (1801) ; Loudon, Arb. et Frut. Brit. 



iii. 1869 (1838); Sargent, Silva N. Amer. viii. 43, tt. 371, 372, 373 (1895), and Trees N. 



Amer. 267 (1905). 

 Quercus olivmformis,^ Michaux f.. Hist. Arb. Am. ii. 32, t. 2 (18 12); Loudon, Arb. et Frut. Brit. 



iii. 1869 (1838). 



A tree occasionally attaining in America 1 70 ft. in height and 20 ft. in girth. 

 Bark, i to 2 in. thick, deeply furrowed, and broken on the surface into irregular 

 flattened scales. Young branchlets stout, with a minute pubescence, gradually dis- 

 appearing in summer. Buds ovoid, \^o\ in. long, greyish tomentose ; the terminal 

 bud surrounded by persistent stipules. Leaves (Plate 336, Fig. 29) deciduous 

 in autumn, turning dull brown before they fall, 6 to 12 in. long, 3 to 6 in. wide, 

 obovate, rounded or acute at the apex ; variable in outline, usually with five to seven 

 lobes, the terminal lobe large, ovate, and crenately toothed, the lower lobes smaller, 

 oblong, and separated by deep sinuses ; occasionally, more regularly divided into 

 more numerous shallower lobes ; upper surface yellowish green, with quickly 

 deciduous scattered hairs ; lower surface pale, covered with a minute appressed 

 pubescence, disappearing in greater part before the end of summer ; petiole stout, 

 pubescent, \ to i in. long. 



Fruit ripening in the first year, solitary or in pairs, sessile or long-stalked, 

 variable in size and shape ; acorn usually broad, ovoid, rounded or depressed at the 

 apex, from \ in. long in the north to 2 in. long in the south ; cupule usually hemi- 

 spheric, thick, pubescent within, covered externally with grey tomentose scales, 

 tuberculate below, prolonged into awn-like tips above, forming a fringed border to 

 the cupule. 



Q. macrocarpa is remarkable for the corky wings ^ on the branchlets, sometimes 

 an inch or more in width, when these are three or four years old. 



A supposed hybrid * between this species and Q. alba was first discovered by 

 M. S. Bebb at Fountaindale, Illinois, and has since been found in other localities. 



' Alton, Hort. Kew. v. 295 (1813). 



' This name was applied by Michaux to trees with deeply lobed leaves and small fruit ; but the foliage is so variable on 

 this species, even on the same individual, that it is doubtful if it can be maintained even as a varietal name. 

 Cf. Miss Gregory, in Bot. Gaz. xiii. 254, pi. xxii. (i888). 

 « Quercus Bebbiana, Schneider, Laubhokkuttde, i. 201 (1904). 



