Sedges differ from grasses by having a 3-angled stem and structurally different flowers where the female flowers are enclosed in a sac like structure called the perigynium, which is subtended by a single scale. Graceful Sedge is a cool season native perennial sedge forming dense clumps. The flowering stems (culms) are triangular in cross-section, 8 to 36 inches high, green in color, usually smooth but within the inflorescence it may have some roughness. These rise from the rhizome and at maturity the flowering stem is much longer than the leaves. Bases are usually purple with blade-less sheaths. There are also non-flowering stems.
The leaf blades are dark-green in color, smooth except the upper parts may have rough margins. They are flat to a flattened M shape, 3 to 9 mm wide and much shorter than the stems.
Leaf sheaths are green, usually smooth or with short hairs. The basal sheaths blade-less and maroon.
The inflorescence consists of both pistillate (female) spikes and a gynecandrous terminal spike, that is, with both staminate (male) and pistillate florets, the pistillate above and the staminate below them. The terminal spike can be 10 to 60 mm long. The lower staminate portion of the terminal spike is the longest part, with the pistillate florets just at the tip. The lower lateral spikes number 2 to 5, are all pistillate, slender, 10 to 70 mm long (usually over 40 mm), linear in shape and on slender stalks as long as the spikes, drooping at maturity, widely separated from each other, one at each stem node. The inflorescence is subtended by a green bracts with sheaths, the lower ones shorter than the inflorescence itself in this species.
Perigynia: The female spikes have many appressed to ascending perigynia, which are green when immature, usually red-dotted, 2-ribbed with 8 to 12 fine veins. (The bladder-like sacs that enclose the female flower and later the fruit are called perigynia, singular - perigynium). They are ovoid-oblong in shape, 2 to 3.7 mm long by 1.3 to 1.6 mm wide, and nearly beak-less and without hair. It loosely envelopes the achene, olive green at maturity. The scales on the perigynia are whitish, sometimes tinged with chestnut brown and with a broad green mid-rib, often red-dotted, ovate to oblong in shape, shorter than the perigynium body with the tips rounded. Stamens number 3 and female flowers have 3 slender white stigmas.
Seed: Female flowers when mature form a dark brown 3-sided achene, 1.2 to 2.6 mm long. Florets are wind pollinated.
Habitat: Graceful Sedge is clump forming with short rhizomes which allow vegetative reproduction forming loose colonies. Graceful Sedge is found in moist to wet woodlands, meadows, swamp and marsh edges. It also adapts to mesic to dry woodland edges. Grows best in partial to full shade.
Names: The genus name, Carex, is from the Latin, being the old name for Sedges. The species, gracillima, means 'most graceful' referring to long stem with drooping spikes. The name of the author for the plant classification, ‘Schwein.’ refers to Lewis David de Schweinitz (1780-1834) German-American botanist and mycologist. Born in the United States and educated in Prussia. His primary work was in mycology.
Comparisons: Graceful Sedge is a member of the section Hymenochlaenae, the characteristics of which are short-rhizomatous root systems, vegetative and flowering stems; sheath fronts hyaline, either white or brownish, blades M shaped; racemose inflorescences with 3 to 7 spikes, upper spikes androgynous, terminal spike staminate or gynecandrous and rarely androgynous; perigynia erect to ascending with 2 strong marginal veins, usually beaked, 3 stigmas; achenes somewhat 3-sided. Of the sedges in this section C. gracillima is best recognized with the gynecandrous terminal spike, the beak-less perigynia, the smooth leaf sheaths and the pendulous spikes. Other look-alike species have perigynia with beaks, leaf sheaths not smooth or bracts longer than the inflorescence. The two closest look-a-likes are C. aestivalis, Summer Sedge, where the perigynia is also without hair but the achenes are 2 to 3.2 mm long and C. roanensis, Roan Mountain Sedge, where the perigynia has hair and the achenes are 3 to 4 mm long. In both of those the achenes are longer and neither is found in Minnesota as both are species of the SE United States.
Above: The drooping narrow spikes on long stems are a field characteristic of this species. Drawing from Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York.
Below: 1st photo - The terminal spike which has pistillate florets at the top and staminate florets below both in flower. 2nd photo - the inflorescence with multiple spikes before elongation of the spike stems.
Below: The stalks of the drooping spikes are as long or almost as long as the spike itself. The perigynia are beak-less. Photo of mature perigynia ©Linda W. Lewis, University of Wisconsin.
Below: Leaf sheaths and blades. Basal sheaths and base of stems are purplish. Blades are a flattened "M" Shape with a definite keel.
Below: Maturing perigynia
Graceful Sedge is one of over 150 sedges native to Minnesota. It is found in the majority of Minnesota Counties with the exception of those in the Southwest section. In North America it is found in the eastern half of the continent except except along the Gulf Coast.
It has been noted in the Garden on both the 1986 and 2009 Garden Plant Census.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"