Flora of North America species comparison

compact, erect to ascending, with cluster of persistent petiole bases of ± equal length;

scales uniformly brown, lanceolate.

compact, erect to ascending, with few to many persistent petiole bases of unequal lengths;

scales uniformly brown or bicolored with dark central stripe and pale brown margins, ovate to narrowly lanceolate.

3.5–15 × 0.5–1.2 cm.

9–35 × 1–8 cm.

green or straw-colored throughout, articulate above base at swollen node, somewhat pliable and resistant to shattering.

usually reddish brown to dark purple proximally when mature, not articulate above base, relatively brittle and easily shattered.

linear to linear-lanceolate, pinnate-pinnatifid proximally, glabrous or with occasional sessile glands, never viscid;

rachis glabrous.

lanceolate to linear-lanceolate, 2-pinnate proximally, moderately glandular, rarely somewhat viscid;

most glandular hairs with thick stalks and distinctly bulbous tips;

rachis usually with abundant glandular and nonglandular hairs.

lanceolate-deltate to ovate, longer than wide, abruptly tapered to a rounded or broadly acute apex, occasionally attenuate;

largest pinnae with 5–14 pairs of pinnules;

abaxial and adaxial surfaces glandular and sparsely villous, with flattened, multicellular hairs concentrated along midribs.

of narrow hairlike segments, these uniseriate throughout, composed of cells many times longer than wide, usually surpassing mature sporangia.

of filamentous or nonfilamentous segments, these multiseriate proximally, often uniseriate distally, composed of ± isodiametric cells, concealed by or slightly surpassing mature sporangia.

averaging 39–45 µm. 2n = 78.

averaging 39–57 µm.

pinnae fan-shaped, wider than long;

distal pinnae ovate-lanceolate, longer than wide, abruptly tapered to a rounded or broadly acute apex;

largest pinnae with 1–3 pairs of pinnules, abaxial and adaxial surfaces glabrous.

entire or broadly crenate;

margins nonlustrous, thin, lacking cilia or translucent projections.

dentate, often shallowly lobed;

margins nonlustrous, thin, slightly glandular and occasionally ciliate with isolated, multicellular hairs, lacking translucent projections.

tips slightly (if at all) enlarged, barely visible adaxially.

tips slightly (if at all) enlarged, barely visible adaxially.