× Quercus dubia Ashe, believed to be a hybrid of Quercus cinerea and Q. laurifolia occurs at Abbottsburg, Bladen County, North Carolina, on the coast of South Carolina, in southern Georgia and northern and central Florida, and at Mississippi City, Lincoln County, Mississippi.
× Quercus subintegra Trel., a supposed hybrid of Quercus cinerea and Q. rubra occurs at Lumber City, Telfair County, Georgia, Lake City, Columbia County, Florida, and at Berlin, Dallas County, Alabama.
× Quercus sublaurifolia Trel., a supposed hybrid of Quercus cinerea and Q. laurifolia occurs at Folkston, Charlton County, Georgia, and at Biloxi, Harrison County, Mississippi.
× Quercus carolinensis Trel., believed to be a hybrid of Quercus cinerea and Q. marilandica occurs at Newbern, Craven County, North Carolina, Lumber City, Telfair County and Climax, Decatur County, Georgia, and near Fletcher, Hardin County, Texas.
× Quercus caduca Trel., believed to be a hybrid of Quercus cinerea and Q. nigra, occurs at Folkston, Charlton County and Lumber City, Telfair County, Georgia, Jacksonville, Duval County, and Gainsville, Alachua County, Florida, Mississippi City, Harrison County, Mississippi, and at Milano, Milano County and Bryan, Brazos County, Texas.
× Quercus oviedoensis Sarg., believed to be a hybrid of Quercus cinerea and Q. myrtifolia, has been found near Oviedo, Orange County, Florida.
20. [Quercus imbricaria] Michx. Shingle Oak. Laurel Oak.
Leaves oblong-lanceolate to oblong-obovate, apiculate and acute or rounded at apex, gradually narrowed and cuneate or rounded at base, entire with slightly thickened, revolute often undulate margins, or sometimes more or less 3-lobed, or on sterile branches occasionally repand-lobulate, when they unfold bright red, soon becoming yellow-green, covered with scurfy rusty pubescence on the upper surface and hoary-tomentose on the lower, at maturity thin, glabrous, dark green, and very lustrous above, pale green or light brown and pubescent below, 4′—6′ long, ¾′—2′ wide, with a stout yellow midrib, numerous slender yellow veins arcuate and united at some distance from the margins, and reticulate veinlets; late in the autumn turning dark red on the upper surface; petioles stout, pubescent, rarely more than ½′ in length. Flowers: staminate in hoary-tomentose aments, 2′—3′ long; calyx light yellow, pubescent, and divided into 4 acute segments; pistillate on slender tomentose peduncles, their involucral scales covered with pale pubescence and about as long as the acute calyx-lobes; stigmas greenish yellow. Fruit solitary or in pairs, on stout peduncles often nearly ½′ in length; nut nearly as broad as long, full and rounded at the ends, dark chestnut-brown, often obscurely striate, ½′—⅔′ long, inclosed for one third to one half its length in a thin cup-shaped or turbinate cup bright red-brown and lustrous on the inner surface, and covered by thin ovate light red-brown scales rounded or acute at the apex and pubescent except on their darker colored margins.
A tree, usually 50°—60° high, with a trunk rarely exceeding 3° in diameter, or rarely 100° high, with a long naked stem 3°—4° in diameter, slender tough horizontal or somewhat pendulous branches forming a narrow round-topped picturesque head, and slender branchlets dark green, lustrous, and often suffused with red when they first appear, soon glabrous, light reddish brown or light brown during their first winter and dark brown in their second year. Winter-buds ovoid, acute, about ⅛′ long, obscurely angled, and covered by closely imbricated light chestnut-brown lustrous scales erose and often ciliate on the margins. Bark on young stems and branches thin, light brown, smooth, and lustrous, becoming on old trunks ¾′—1½′ thick, and slightly divided by irregular shallow fissures into broad ridges covered by close slightly appressed light brown scales somewhat tinged with red. Wood heavy, hard, rather coarse-grained, light brown tinged with red, with thin lighter colored sapwood; occasionally used in construction, and for clapboards and shingles.