Flora of North America species comparison

usually prostrate to erect, sometimes scandent, not scapose, rarely with recurved spines (some species of Persicaria), glabrous or pubescent, sometimes glandular;

nodes usually swollen;

branches free (adnate to stems distal to nodes and appearing to arise internodally in Polygonella);

tendrils absent (except in Antigonon and Brunnichia).

ocrea persistent or deciduous, tan or greenish brown, cylindric, 2–4 mm, margins oblique, face not fringed with reflexed hairs and slender bristles at base, otherwise glabrous or scabrid;

petiole 0.5–5 cm, puberulent in lines;

blade cordate-ovate, cordate-hastate, or sagittate, 2–6(–15) × 2–5(–10) cm, base cordate, margins wavy, scabrid, apex acuminate, abaxial face usually mealy and, rarely, minutely dotted, not glaucous, adaxial face glabrous.

deciduous (persistent in Coccoloba and sometimes more than 1 year in Antigonon and Polygonella), basal or basal and cauline, rarely cauline only, mostly alternate;

ocrea present, persistent or deciduous, cylindric to funnelform, chartaceous, membranous, coriaceous, or, rarely, foliaceous or partly so;

petiole present or absent, rarely articulate basally (Fagopyrum, Fallopia, Polygonella, Polygonum), rarely with extrafloral nectaries (Fallopia, Muehlenbeckia);

blade simple with entire margins, rarely undulate or lobed.

axillary, erect or spreading, spikelike, 2–10(–15) cm, axes puberulent;

peduncle 0.1–10 cm or absent, glabrous or scabrid distally in lines.

terminal or terminal and axillary, spikelike, racemelike, paniclelike, cymelike, or, rarely, capitate, comprising simple or branched clusters of compound inflorescences;

bracts absent;

peduncle spreading to erect, sometimes absent;

clusters of flowers subtended by connate bracteoles forming persistent membranous tube (ocreola), awnless.

ascending or spreading, articulated distally, 1–3 mm, glabrous or, rarely, scabrid.

bisexual, 3–6 per ocreate fascicle;

perianth nonaccrescent, greenish white, often with pinkish or purplish base, 3–5 mm including stipelike base, glabrous or outer 3 with blunt, hyaline hairs;

tepals elliptic to obovate, apex obtuse to acute, outer 3 obscurely keeled;

stamens 8;

filaments flattened proximally, glabrous;

styles connate distally;

stigmas capitate.

usually bisexual, sometimes bisexual and unisexual on same plant, rarely unisexual only, 1–20+ per ocreate fascicle, often with stipelike base distal to articulation;

perianth often accrescent in fruit, often greenish, white, pink, yellow, red, or purple, usually unwinged and unkeeled (winged or, sometimes, keeled in Fallopia, rarely keeled in Polygonum), campanulate or urceolate, sometimes membranous, indurate, or fleshy in fruit, rarely developing raised tubercles proximally (Rumex), glabrous or pubescent, sometimes glandular or glandular-punctate;

tepals 2–6, usually in 2 whorls, distinct or connate proximally and forming tube, petaloid or sepaloid, monomorphic or dimorphic;

nectary a disk at base of ovary or glands associated with bases of filaments;

stamens usually (1–)6–9, staminodes rarely present;

filaments distinct, or connate basally and sometimes forming staminal tube, free or adnate to perianth tube;

pistils (2–)3(–4)-carpellate;

ovary 1-locular (sometimes with vestigial partitions proximally);

ovule 1, orthotropous or, rarely, anatropous, placentation basal or free-central;

styles 1–3, erect to spreading or recurved, distinct or connate proximally;

stigmas peltate, capitate, fimbriate, or penicillate.

included, black, 4–5(–6) × 1.8–2.3 mm, dull, minutely granular-tuberculate, especially on faces; fruiting perianth glabrous or with blunt, hyaline hairs, wings absent or, rarely, flat to undulate, 0.4–0.9 mm wide at maturity, scarcely decurrent on stipelike base, margins entire.

yellowish, brown, red, or black, homocarpic (sometimes heterocarpic in Polygonum), winged or unwinged, usually 2–3-gonous, sometimes discoid, biconvex, or spheroidal, rarely 4-gonous.

embryo usually straight or curved, rarely folded.

= 40.