Northern Prairie Wildlife Research Center
Aquatic and Wetland Vascular Plants of the Northern Great Plains
Physostegia Benth. -- Obedient plant
Stout, erect, perennial herbs; stems arising singly from slender rhizomes
or from a slender caudex, simple throughout or branched at the base of the inflorescence.
Leaves sessile or the lowermost sometimes short-petioled, elliptic to
lanceolate or oblanceolate, mostly serrate. Flowers showy, pinkish-lavender
to purple-lavender, short-pedicelled and borne singly in the axils of short
bracts, arranged in 1-several terminal and lateral, spikelike racemes. Calyx
regular or nearly so, tubular-campanulate, 5-toothed, the teeth much shorter
than the tube; corolla bilabiate, much longer than the calyx, the upper
lip hoodlike, entire to emarginate, the lower lip about equaling or shorter
than the upper, shallowly 3-lobed; stamens 4, included or slightly exserted
under the upper corolla lip; stigma 2-lobed, style about equaling the
stamens. Nutlets ovoid, unequally trigonous, smooth.
Cantino, P. D. 1981. Change of status for Physostegia virginiana
var. ledinghamii (Labiatae) and evidence for a hybrid
origin. Rhodora 83:111-118.
Lundell, C. L. 1959. Studies in Physostegia I. New species and
observations on others. Wrightia 2:4-12.
||Upper leaves clasping the stem, some of them usually
broadest near the base of the blade; corolla usually with some stipitate
glands (often lacking in P. ledinghamii); rare species in our
||Upper leaves not clasping the stem, broadest at
the middle or above; corolla glabrous or sparsely puberulent but lacking
stipitate glands; common species.
||Corolla 14-23 mm long, often lacking stipitate glands;
nutlets 2.8-4 mm long.
||Corolla 9-16 mm long, usually with stipitate glands;
nutlets 2.1-3.3 mm long.
41. Lamiaceae, the Mint Family
3. Physostegia Benth. -- Obedient plant
- 1. Physostegia ledinghammii (Boivin)
- 2. Physostegia parviflora Nutt.
ex A. Gray
- 3. Physostegia virginiana (L.) Benth.
Return to Family -- Lamiaceae - The Mint Family
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