Flora of North America species comparison

ascending or prostrate, profusely branched basally, radiating from rootstock, mostly 0.2–0.5 m.

erect or sometimes ascending proximally, much-branched and bushy, rarely nearly simple, 0.3–1(–2) m; each node with paired, divergent spines (modified bracts) to 1.5(–2.5) cm.

petiole 1/2 as long as to equaling blade;

blade rhombic-ovate or ovate to lanceolate, 1–2 × 0.5–1 cm, base tapering or cuneate, margins entire, plane or slightly undulate, apex subacute, obtuse, or retuse or shallowly emarginate, mucronulate.

petiole ± equaling or longer than blade;

blade rhombic-ovate, ovate, or ovate-lanceolate, 3–10(–15) × 1.5–6 cm, base broadly cuneate, margins entire, plane or slightly undulate, apex acute or subobtuse to indistinctly emarginate, mucronulate.

of pistillate flowers linear, 0.5–1 mm, 1/2 as long as tepals.

of pistillate flowers lanceolate to ovate-lanceolate, shorter than tepals, apex attenuate.

terminal, erect, compact, pyramidal panicles and also some axillary clusters, green or silvery green, occasionally tinged with red, leafless at least distally.

simple or compound terminal staminate spikes and axillary subglobose mostly pistillate clusters, erect or with reflexed or nodding tips, usually green to silvery green.

clustered at tips of inflorescences;

tepals 2–3;

stamens 2–3.

often terminal or in proximal glomerules;

tepals 5, equal or subequal, 1.7–2.5 mm;

stamens 5.

tepals 2–3, narrowly elliptic or oblanceolate, not clawed, equal or subequal, 1.2–2 mm, apex broadly acute;

style branches erect;

stigmas 3.

tepals 5, obovate-lanceolate or spatulate-lanceolate, equal or subequal, 1.2–2 mm, apex mucronate or short-aristate;

styles erect or spreading;

stigmas 3.

very dark brown to black, 1–1.2 mm diam., shiny, filling only proximal portion of fruit.

black, lenticular or subglobose-lenticular, 0.7–1 mm diam., smooth, shiny.

marked with 2(–3) green lines that intersect at apex and divide fruit into halves or quarters, slightly to distinctly inflated, ellipsoid, 2–3 mm, distinctly longer than tepals, smooth (in dry plants wrinkled or rugose), indehiscent.

ovoid to subglobose, 1.5–2.5 mm, membranaceous proximally, wrinkled and spongy or inflated distally, irregularly dehiscent or indehiscent.