• NSF NEON | Open Data to Understand our Ecosystems
  • Biorepository Data Portal

  • Home
  • Search
    • Sample search
    • Map search
    • Dynamic Species List
    • Taxonomic Explorer
  • Images
    • Image Browser
    • Image Search
  • Datasets
    • Research Datasets and Special Collections
    • Checklist: Research Sites - Invertebrates
    • Checklist: Research Sites - Plants
    • Checklist: Research Sites - Vertebrates
  • Sample Use
    • Sample Use Policy
    • Sample Request
    • Sample Archival Request
    • Data Usage Policy
  • Additional Information
    • Tutorials and Help
    • About NEON
    • NEON Data Portal
    • ASU Biocollections
    • About Symbiota
  • Getting Started
Login New Account Sitemap
Quercus phellos L.  

Explore 3 occurrences

Family: Fagaceae
willow oak
Quercus phellos image
  • FNA
  • Gleason & Cronquist
  • Resources
Kevin C. Nixon in Flora of North America (vol. 3)
Trees , deciduous, to 30 m. Bark dark gray and smooth, becoming darker and irregularly fissured with age, inner bark light orange. Twigs reddish brown, 1-2 mm diam., glabrous. Terminal buds chestnut brown, ovoid, 2-4 mm, apex acute, glabrous. Leaves: petiole 2-4(-6) mm, glabrous, rarely sparsely hairy. Leaf blade linear to narrowly elliptic, usually widest near middle, 50-120 × 10-25 mm, base acute, margins entire with 1 apical awn, apex acute; surfaces abaxially pale green, glabrous, rarely softly pubescent, adaxially light green, glabrous. Acorns biennial; cup shallowly saucer-shaped, 3-6.5 mm high × 7.5-11 mm wide, covering 1/4-1/3 nut, outer surface puberulent, inner surface light brown, pubescent, scale tips tightly appressed, acute; nut ovoid to hemispheric, 8-12 × 6.5-10 mm, often striate, glabrate, scar diam. 4.5-6 mm. Flowering spring. Of bottomland flood plains, also on stream banks, dunes, and terraces, and, occasionally, on poorly drained uplands; 0-400 m; Ala., Ark., Del., D.C., Fla., Ga., Ill., Ky., La., Md., Miss., Mo., N.J., N.Y., N.C., Okla., Pa., S.C., Tenn., Tex., Va. Individual trees with leaves softly pubescent abaxially may be classified as Quercus phellos forma intonsa Fernald; however, such leaves are known to occur on second-flush shoots from twigs bearing typical leaves. Quercus phellos reportedly hybridizes with Q . coccinea (W. W. Ashe 1894); with Q . ilicifolia (= Q . × giffordi Trelease) and Q . incana (E. J. Palmer 1948); and with Q . marilandica , Q . nigra , Q . pagoda (= Q . × ludoviciana Sargent), Q . palustris , Q . rubra , Q . shumardii , and Q . velutina . D. M. Hunt (1989) cited evidence of hybridization also with Q . hemisphaerica , Q . imbricaria , Q . laurifolia , and Q . pumila .

Vascular plants of NE US and adjacent Canada
Tall shrub, or tree to 25 m; twigs of the season reddish-brown, glabrous; lvs shiny-green above, thin, oblong-linear to lanceolate or oblanceolate, 6-12 נ1-2(-2.5) cm, bristle-tipped, entire, usually cuneate at base, glabrous above with finely reticulate, elevated veinlets, dull (and somewhat paler) green beneath and glabrous or with the stellate pubescence persistent especially in the vein-axils or along the midvein; acorns 1-1.5 cm, the cup shallowly saucer-shaped, its scales closely appressed, pubescent except at the margin. Swamps and moist soil; s. N.Y. to Fla. and Tex., chiefly on the coastal plain, n. in the interior to s. Ill.

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

©The New York Botanical Garden. All rights reserved. Used by permission.
Quercus phellos
Open Interactive Map
Quercus phellos image
Quercus phellos image
Click to Display
3 Total Images
NSF NEON | Open Data to Understand our Ecosystems The National Ecological Observatory Network is a major facility fully funded by the National Science Foundation. Any opinions, findings and conclusions or recommendations expressed in this material do not necessarily reflect the views of the National Science Foundation.