• Authority

    Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

  • Family


  • Scientific Name

    Quercus L.

  • Description

    Genus Description - Staminate fls in slender, naked catkins, the bracts caducous or none, the cal divided to the base into 6(3–7) segments; stamens 3–12; pistillate fls solitary or in small spikes, each subtended by a bract and surrounded by an involucre of many scales; ovary 3-locular; nut subtended and partly enclosed by the accrescent involucre; trees or shrubs, the fls appearing before the lvs; 2n=24. 400+, cosmop.

  • Discussion

    Our oaks fall into 2 subgenera: in Quercus, the white oaks (spp. 1–12), the fr matures at the end of the first season, the stigmas are sessile or nearly so, the abortive ovules lie at the base of the seed, and the lvs or their lobes are not bristle-tipped. In Erythrobalanus, the red and black oaks (spp. 13–28), the fr matures during the second year, the styles are elongate, the abortive ovules lie at the top of the seed, and in most spp. the lvs or their lobes are bristle-tipped.

    Most or all of the spp. within each subgenus can and frequently do hybridize, but natural intersubgeneric hybrids are unknown. The following names are believed to apply to hybrids as indicated:

    Q. ×asheana Little = Q. cinerea × laevis

    Q. ×atlantica Ashe = Q. cinerea × laurifolia

    Q. ×beadlei Trel. = Q. alba × michauxii

    Q. ×bebbiana C. K. Schneid. = Q. alba × macrocarpa

    Q. ×benderi Baen. = Q. coccinea × rubra

    Q. ×blufftonensis Trel. = Q. falcata × laevis

    Q. ×brittonii W. T. Davis = Q. ilicifolia × marilandica

    Q. ×bushii Sarg. = Q. marilandica × velutina

    Q. ×byarsii Sudw. = Q. macrocarpa × michauxii

    Q. ×caduca Trel. = Q. cinerea × nigra

    Q. ×cocksii Sarg. = Q. laurifolia × velutina

    Q. ×comptoniae Sarg. = Q. lyrata × virginiana

    Q. ×cravenensis Little = Q. cinerea × marilandica Q. ×deamii Trel. = Q. macrocarpa × muehlenbergii Q. ×demarei Ashe = Q. nigra × velutina

    Q. ×dubia Ashe = Q. phellos × velutina or laevis Q. ×egglestonii Trel. = Q. imbricaria × shumardii Q. ×exacta Trel. = Q. imbricaria × palustris

    Q. ×faxonii Trel. = Q. alba × prinoides Q. ×fernaldii Trel. = Q. ilicifolia × rubra Q. ×fernowii Trel. = Q. alba × stellata

    Q. ×filialis Little = Q. phellos × velutina

  • Common Names