Flora of North America species comparison

radially symmetric, underground (rhizomatous) and aerial, not readily fragmenting, irregularly forked;

both rhizomatous and aerial stems often with 1 branch arrested, budlike, tips straight; rhizomatous stems hard to distinguish on wholly creeping plants;

aerial stems erect or ascending, sometimes decumbent to slightly creeping, budlike arrested branches restricted mostly near stem base.

not readily fragmenting, prostrate, upperside and underside structurally different, irregularly forked, branches determinate, tips upturned.

dimorphic, not clearly ranked.

dimorphic, arranged in 8 ranks, tightly appressed, ascending, green;

abaxial ridges absent;

apex with yellowish bristle 0.2–0.5 mm, becoming denticulate (by breaking off of bristle);

bristle usually more persistent in underside leaves.

solitary, 0.5–2.5(–3.5) cm;

sporophylls lanceolate, strongly tapering toward tip, abaxial ridges prominent, base glabrous, margins short-ciliate, apex long-bristled.

solitary, (0.7–)1.5–2(–2.6) cm;

sporophylls lanceolate, abaxial ridges not prominent, base glabrous, margins ciliate, apex strongly tapering, bristle obscure.

borne on upperside of stems, restricted to lower stems or throughout stem length, 0.3–0.5 mm diam.

borne on upperside of stems, throughout stem length, 0.25–0.37 mm diam.

stem leaves persistent or deciduous, tightly appressed, scalelike.

stem leaves appressed, ascending, green, linear-lanceolate, 3–4.7 × 0.45–0.65 mm;

abaxial ridges present;

base abruptly adnate, rounded, pubescent;

margins long-ciliate, cilia white to whitish, spreading, 0.1–0.2 mm;

apex not keeled to slightly keeled;

bristle white to whitish or yellowish to greenish near base, puberulent, 0.65–1.85 mm (1/3–1/2 length of leaves).

leaves narrowly linear-lanceolate to falcate (on marginal ranks), 3.5–4.5(–5) X 0.55–0.7 mm;

base abruptly adnate or slightly decurrent, usually pubescent, sometimes glabrous;

margins ciliate, cilia transparent, spreading, 0.12–0.26 mm.

leaves linear-lanceolate, 3.3–3.85 × 0.6–0.75 mm;

base abruptly adnate, pubescent;

margins ciliate, cilia transparent, spreading, 0.12–0.26 mm.