18. Quércus imbricària, Michx. (Laurel-or Shingle-oak.) Leaves lanceolate-oblong, entire, tipped with an abrupt, sharp point, pale-downy beneath. Acorn globular, 5/8 in. long, cup with broad, whitish, close-pressed scales, covering about one third of the nut. A stout tree, 30 to 50 ft. high, found in barrens and open woodlands. Wood extensively used in the West for shingles. New Jersey to Wisconsin, and southward.
Q. Phéllos.
19. Quércus Phéllos, L. (Willow-oak.) Leaves 2 to 4 in. long, thick, linear-lanceolate, narrowed at both ends, entire or very nearly so, soon smooth, light green, bristle-tipped, willow-like, scurfy when young. Acorns about sessile, globular, small (½ in.), in a shallow saucer shaped cup; on the old wood. Tree 30 to 50 ft. high, with smooth, thick bark, and reddish, coarse-grained wood, of little value. Borders of swamps, New Jersey, south and west; also cultivated.
Q. Ròbur.
20. Quércus Ròbur, L. (English Oak.) Leaves on short footstalks, oblong, smooth, dilated upward, sinuately lobed, hardly pinnatifid. Acorns in the axils of the leaves of the year, ovate-oblong, over 1 in., about one third inclosed in the hemispherical cup; sessile in var. sessiliflora; clustered and long-peduncled in var. pedunculata. Trees 50 to 100 ft. high, extensively cultivated; from Europe; the nursery catalogues name as many as a score or more varieties.
One var., fastigiata (Pyramidal Oak), is a peculiar upright tree like the Lombardy Poplar; var. pendula (Weeping Oak) has long, slender, drooping branches.
Q. Cérris.