Stachys arvensis

Herb with stems decumbent to ascending, many-branched, 2-6 dm long, hirsute. Leaves ovate to narrowly ovate, 1-3.5(-6) cm long, 0.6-2.3(-3.5) cm wide, hirsute, more densely so along veins on lower surface, margins crenate, apex rounded, base truncate to subcordate, petioles 0-2(-3.5) cm long. Flowers usually 3-6 in verticillasters, these arranged in terminal, leafy, spike-like inflorescences, calyx usually tinged purple, campanulate, 5-6 mm long, hirsute, especially along nerves, cleft ca. 1/2 its length, the teeth slightly unequal, lanceolate, upper lobes ca. 2.7-2.8 mm long, lower lobe ca. 2.2-2.3 mm long, corolla pink, rose, or blue, 5-7 mm long, upper lip erect, median lobe of lower lip ovate, faintly spotted red near base. Nutlets black, shiny, muricate, obovoid, ca. 2 mm long. [Wagner et al., 2014]