Chelone glabra L.
Family - Plantaginaceae
Stems - To 1.5 m, ascending to erect, sometimes sprawling with age, mostly unbranched, glabrous.
Leaves - Opposite, simple, sessile to short-petiolate, lanceolate, sharply pointed, margins sharply toothed to nearly entire, usually glabrous.
Inflorescence - Dense terminal spikes to 9 cm long, usually subtended by a pair of bracts similar to the stem leaves. Flowers subtended by 2 or 3 sepaloid bractlets immediately beneath calyx, these ovate, pointed at tip, to 1 cm long.
Flowers - Calyces 5-11 mm long, deeply 5-lobed, the lobe margins sometimes thin and translucent, glabrous or minutely short-hairy. Corollas 25-35 mm long, bilabiate, 5-lobed but often appearing more or less 4-lobed, glabrous externally, the tube longer than the lobes, white or pale cream colored, occasionally greenish or pinkish, the lower lip shallowly 3-lobed and bearded with woolly hairs, the upper lip slightly to moderately keeled and arched downward or slightly helmet-shaped, minutely notched to shallowly 2- lobed at the tip. Fertile stamens 4 with anther sacs densely wooly. Staminode 1, green, glabrous. Style 1, not exserted, the stigma capitate, unlobed.
Calyces and bractlets.
Flowering - July - October.
Habitat - Fens, streambanks, bottomland forests.
Origin - Native to the U.S.
Other info. - This striking species can be found in a few scattered counties throughout Missouri but is generally uncommon. The plant grows well from seed and would do well in in cultivation as a pond margin plant. C. glabra is a highly variable plant. The leaves may be pubescent or not and have many different shapes. The corollas can range from green to pinkish or white. Several different forms and varieties have been described based upon these differences, but the degree of morphological intergradation discourages their formal recognition.
Photographs taken at Mountain Longleaf National Wildlife Refuge, AL., 10-2-05 (DETenaglia); also at Shaw Nature Reserve, Franklin County, MO, 9-2-2015 (SRTurner).