Flora of North America species comparison

alternate or whorled, rigid, angle of divergence about 30°.

alternate or whorled, semiflexible to rigid, angle of divergence about 45°.

pale green, becoming yellow, then gray with age, glaucous, with numerous very fine longitudinal grooves;

internodes 3–10 cm.

yellow-green, becoming yellow, then yellow-brown with age, glaucous, with numerous very fine longitudinal grooves;

internodes 3–10 cm.

in whorls of 3, 5–15 mm, connate to 1/2–3/4 their length;

bases becoming gray and shredded with age;

apex spinose.

in whorls of 3, 2–6 mm, connate to 1/2–3/4 their length;

bases at first membranous, then becoming thickened, completely deciduous;

apex acute.

1–several at node, obovoid, 6–10 mm, on short, scaly peduncles;

bracts in 8–12 whorls of 3, reddish brown, obovate, slightly clawed, 3–4 × 2–3 mm, membranous;

bracteoles nearly equaling bracts;

sporangiophores 4–5 mm, exserted to 1/4 their length, with 4–5 short-stalked microsporangia.

1–several at node, ovoid, 6–8 mm, on short, scaly peduncles;

bracts in 8–12 whorls of 3, light orange-yellow, ovate, 2–3 × 2–3 mm, membranous, slightly united at base;

bracteoles equaling or slightly exceeding bracts;

sporangiophores 3–5 mm, exserted to 1/3 their length, with 3–7 sessile to short-stalked microsporangia.

cones 1–several at node, obovoid, 10–15 mm, on short, scaly peduncles (rarely sessile);

bracts in 6–9 whorls of 3, circular, 8–12 × 8–12 mm, papery, translucent with reddish brown center and base, base clawed, margins entire.

cones 1–several at node, ovoid, 8–10 mm, on very short, scaly peduncles;

bracts in 4–6 whorls of 3, circular, 5–7 × 5–10 mm, papery, with orange- to green-yellow center and base, slightly clawed, margins entire.

buds spinelike, to 10 mm.

buds conic, 2–3 mm, apex acute.