cuptTLiFERji:. (oak family.) 475 



Minn., Iowa, E.Kan., and Tex. Tree or shrub, 10-45° high, with ridged 

 trunk, and very hard wood. 



6. QUE Reus, L. Oak. 



Sterile flowers in slender naked catkins ; Ijracts caducous ; calyx 2 - 8-partea 

 or lobed ; stamens 3 - 12 ; anthers 2-celled. Fertile flowers scattered or some- 

 what clustered, consi.sting of a nearly 3-celled and 6-ovuled ovary, with a .3-lubed 

 stigma, enclosed by a scalv bud-like involucre which becomes an indurated cup 

 (cupa/e) around the base of the rounded nut or acorn. Cotyledons remainijig 

 underground in germination ; radicle very short, included. — Flowers greenish 

 or yellowish. Sterile catkins single or often several from the same lateral scaly 

 bud, filiform and hanging in all our species. (The classical Latin name.) AD 

 flower in spring, and shed their nuts in Oct. of the same or the next year. 

 § 1. LEUCOBALANUS. Bark pale, often scahj ; leaves and their lobes or 

 teeth obtuse, never bristle-pointed ; stamens 6-8; scales of the cup more or 

 less knobbij at base; stigmas sessile or nearly so ; abortive ovules at the base 

 of the perfect seed ; inner surface of nut glabrous ; fruit maturing the first 

 year, often peduncle d ; kernel commonly sweetish; wood tough and dense. 

 * Leaves deciduous, I y rate or sinuate-pinnatifid, pale beneath. — ^YHITE Oaks. 



1. Q. alba, L. (White Oak.) Mature leaves smooth, pale or glaucous 

 underneath, bright green above, obovate-oblong, obliquely cut into 3-9 oblong 

 or linear and obtuse mostly entire lobes ; cup hemisplLerical-saucer-shaped, rough 

 or tubercled at maturity, naked, much shorter than the ovoid or oblong acorn 

 (r long). — All soils, Maine to S. E. Minn., E. Kan., and south to the Gulf. A 

 large and valuable tree; lobes of the leaves short and broad (3-5), or deep 

 and narrow ( 5 - 9 ) . 



2. Q. Stellata, Wang. (Post Oak. Iron Oak.) Leaves grayish or 

 yellowish-downy underneath, pale and rough cdiove, thickish, sinuately cut into 

 5-7 rounded divergent lobes, the upper ones much larger and often 1-3- 

 notched ; cup deep saucer-shaped , naked, one third or half the length of the ovoid 

 acorn (6-9" long). (Q. obtusiloba, Michx.) — Sandy or sterile soil, Martha's 

 Vineyard to Mich, and E. Xeb., south to Fla. and Tex.; common, especially 

 southward. A small tree with very durable wood. 



3. Q. maerocarpa, Miclix. (Bur Oak. Over-cup or Mossy-cup Oak.) 

 Leaves obovate or oblong, I yratel y-pinnatifid or deeply sinuate-lobed, or nearly 

 parted, sometimes nearly entire, irregular, downy or pale beneath ; the lobes 

 sparingly and obtusely toothed, or the smaller ones entire ; cup deep, thick and 

 woody (9"- 2' across), conspicuously imbricated with hard and thick pointed 

 scales, the upper ones aivned, so as usually to make a mossy-fringed border ; acorn 

 broadly ovoid (1 - 1+' long), half immersed in or entirely enclosed by the cup. — 

 Eich soil, N. Scotia to W. Mass. and Penn., west to ]\Iinn., central Xeb., and 

 Kan. A large and valuable tree ; extremely variable in the size and fringe of 

 the acorns. — Yar. oliv.eformis, Gray, is only a narrower-leaved form with 

 unusually small oblong acorns. 



4. Q. lyrata, Walt. (Ovep-cup Oak. Swamp Post Oak.) Leaves 

 crowded at the end of the branchlets, obovate-oblong, acute at base, more or less 

 deeply 7 -d-lohed, white-tomentose beneath or at length smoothish, the lobes trian- 

 gular to oblong, acute or obtuse, entire or sparingly toothed ; fruit short-peduncled 



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