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Pteridium
Family: Dennstaedtiaceae
Pteridium image
Max Licher
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Carol A. Jacobs
James H. Peck in Flora of North America (vol. 2)
Plants terrestrial, often forming colonies or thickets. Stems subterranean, slender, long-creeping; hairs pale to dark, jointed; scales absent; true vessels present (absent in other Dennstaedtiaceae genera in the flora). Leaves widely spaced, broadly deltate, 0.5--4.5 m. Petiole glabrous to short-hairy, without prickles, with stem buds near base, vascular bundles numerous, U- or O-shaped in cross section. Blade 2--4-pinnate, rachis and costae grooved adaxially; rachis without prickles; nectaries at base of proximal and sometimes distal pinnae. Segments pinnately divided, ultimate segments ovate to oblong to linear, base extending proximally on costae (decurrent) or proximally (surcurrent), margins entire. Veins free or joined at margin by commissural vein beneath sori, pinnately 2--3-forked. Sori ± continuous, covered by recurved, outer false indusium and obscure, extrorse, inner true indusium. Spores tetrahedral-globose, trilete, very finely granulate. x = 26.
Vascular plants of NE US and adjacent Canada
Petiole coarse, ±erect and stem-like, with several vascular bundles that unite distally to form a gutter-shaped bundle; blade ternate- pinnately 2-3 times compound, the ultimate segments pinnatifid but otherwise entire; pinnae opposite or nearly so; pinnules alternate, their segments oblong to linear with revolute margins; veins "free" but connected by a submarginal vascular strand on which the contiguous and confluent linear sori are borne, these protected by the recurved, modified lf-margin and a minute or often nearly obsolete hyaline inner indusial flap of tissue; coarse ferns with widely creeping rhizomes and coriaceous, deciduous lvs, the rhizome and often also the lvs provided with septate hairs. 1-several, by interpretation, cosmop.

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.
Species within inventory project: North American Species Lists
Pteridium aquilinum
Image of Pteridium aquilinum

The PCC, and this data portal, were made possible by funding from the National Science Foundation’s Advancing Digitization of Biological Collections (ADBC) program, grant numbers 1802504, 1802352, 1802134, 1802033, 1802270, 1802255, 1802239, 1802446, 1802305.
The pteridoportal taxonomic thesaurus is based on the Checklist of Ferns and Lycophytes of the World, generously provided by Michael Hassler.