Pteridium

Gleditsch ex Scopoli

Fl. Carniol. 169. 1760.

Etymology: Greek pteridion, a small fern
Treatment appears in FNA Volume 2.
 TaxonIllustrator 
FNA2 P30 Pteridium pg 203.jpegPteridium aquilinum var. latiusculum
Pteridium aquilinum var. pseudocaudatum
Pteridium aquilinum var. caudatum
John Myers
John Myers
John Myers

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.

Distribution

Almost worldwide

Discussion

Species 1 (1 species, 4 varieties in the flora).

... more about "Pteridium"
Carol A. Jacobs +  and James H. Peck +
Gleditsch ex Scopoli +
1-pinnate;decompound +
with mixture +, hairy +  and glabrous +
Almost worldwide +
Greek pteridion, a small fern +
pale +  and dark +
fused +  and free +
monomorphic +
deltate +
50 cm500 mm <br />0.5 m <br /> (450 cm4,500 mm <br />4.5 m <br />) +
not articulate +
glabrous +  and short-hairy +
Fl. Carniol. +
page1976a +, perring1976a +  and tryon1941a +
tetrahedral-globose +
granulate +
branching +  and solenostelic +
subterranean +
slender +
Pteridium +
Dennstaedtiaceae +
o--shaped +  and u +
forking +  and pinnate +
joined +  and free +
2-3-forked +