Flora of North America species comparison

suberect, prostrate, or scandent, glabrous or puberulent, sometimes papillose.

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).

deciduous, cauline, alternate, usually petiolate;

ocrea usually deciduous, sometimes persistent, chartaceous;

petiole base articulated, extrafloral nectaries present;

blade linear to orbiculate, panduriform, or triangular-lanceolate, margins entire or irregularly wavy.

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.

terminal and axillary, spikelike, essentially not pedunculate.

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.

prescent.

bisexual and unisexual, with staminate, pistillate, or sometimes both sexes occurring with bisexual flowers on the same plant, 1–2(–5) per ocreate fascicle, base stipelike;

perianth accrescent, white to greenish white, campanulate, glabrous;

tepals 5, connate proximally, sepaloid, dimorphic, outer slightly larger than inner.

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.

stamens 8 (9);

filaments distinct, adnate to base of perianth tube, glabrous;

anthers yellow or pink to purple, ovate to elliptic;

pistil rudimentary.

tube white or reddish purple to black in fruit, becoming fleshy;

stamens rudimentary;

styles 3, spreading, connate proximally;

stigmas fimbriate.

completely or partly included in fleshy perianth, black or dark brown, unwinged, 3-gonous to subglobose, glabrous.

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 straight.

embryo usually straight or curved, rarely folded.

= 10.