Margins nearly smooth to shallowly wavy coarse-toothed. Stems highly branched. Margins typically wavy, sometimes coarse-toothed. Taproot thick, deeply penetrates soil, often develops stems several centimeters below ground. Underground stems often become rhizomatous and develop new plants.
Rhizomes spread aggressively , producing many new plants.
Flowers open near sunset and wither the following morning. Flowers irregular . Stamens 8, with paired teeth at filament bases. Racemes sometimes branched, drooping at the tips. Petals 3-8 mm long.