Greater marsh

Description

Herbs erect, to 10 dm, sometimes with ascending branches in distal 1/2+. Stems: internodes 4-lined at first, then terete. Leaves petiolate, petiole 2-15 mm; blade narrowly elliptic to narrowly oblong, 30-150 - 10-35 mm, base cuneate, apex rounded, gland dots laminar and intramarginal. Inflorescences interrupted spiciform-cylindric, 3-flowered from terminal node, sometimes with subsessile flowers or pedunculate triads and/or flowering branches from to 8 proximal nodes. Flowers 7-10 mm diam.; sepals narrowly oblong to narrowly elliptic or lanceolate, 3-5 - 1-1.5 mm, apex obtuse to rounded; petals narrowly obovate, 5-7 mm; stamen fascicles 3-5 mm; filaments 1/2+ connate; styles 0.8-1.2 mm. Capsules cylindric, 7-12 - 3-4 mm, apex subacute. Seeds 0.8-1.1 mm.