Sedge family (Cyperaceae)
Description: This native perennial sedge forms a small loose tuft of leafy culms about ½1½' tall; both fertile and vegetative shoots occur. Each culm is unbranched, light green, sharply 3-angled, and glabrous; there are several alternate leaves along its length. The leaf blades are 1-3 mm. across and usually shorter than the culms; they are light to medium green, glabrous, and channeled along their midveins. These blades are ascending to widely spreading. The leaf sheaths are light green, finely veined, and glabrous. Each fertile culm terminates in an inflorescence consisting of a terminal staminate spikelet, 2-3 pistillate spikelets, and their bracts (see photo of Early Inflorescence). The narrow staminate spikelet is 1.02.5 cm. long on a short peduncle. The staminate scales of this spikelet are 3.55.0 mm. long, 1.5 mm. across, and lanceolate or elliptic in shape; they are dark purple during the blooming period, often with green midveins and membranous margins. The large anthers of the staminate florets are cream-colored and linear in shape; they become dull light brown with age. The sessile pistillate spikelets are much smaller in size than the staminate spikelet; they are adjacent to each other or slightly separated. Each pistillate spikelet has about 4-12 perigynia and their scales. The perigynia are 2.53.0 mm. long and 1.5 mm. across; they are ovoid-globoid with short stout beaks and stipe-like bases that are also short and stout. The surface of each immature perigynium is light green and either glabrous or finely short-pubescent. The pistillate scales are about the same length as the perigynia; they are ovate in shape, dark purple, and membranous along their margins. Each pistillate floret has 3 styles that are slender and white. At the base of the lowest pistillate spikelet, there is a green to purple leafy bract that is as long or a little longer than the spikelet (up to 1 cm. in length). Other bracts of the inflorescence are smaller in size and often scale-like. The blooming period occurs from mid- to late spring and lasts about 1-2 weeks. The pistillate florets are wind-pollinated. The achenes are about 1.52.0 mm. long, globoid-obovoid in shape, and slightly 3-angled. The root system produces long stolons than run along the surface of the soil (underneath fallen leaves and other debris). Loose vegetative colonies are often formed from these stolons.
Cultivation: Pennsylvania Sedge prefers partial or dappled sunlight and mesic to dry conditions with good drainage. A sandy loam or loose loam with abundant organic matter is preferred; this sedge also adapts to thin rocky soil if there is a layer of loam and decaying organic matter on top.
Range & Habitat: Pennsylvania Sedge is occasional to locally common in most areas of Illinois; it is least common in south-central Illinois (see Distribution Map). Habitats include open upland woodlands, thinly wooded bluffs, wooded slopes, sandy savannas, and rocky or sandy openings in wooded areas. This sedge is found in areas where Oak trees are commonly present.
Faunal Associations: Insects that are known to feed on Pennsylvania Sedge include the leafhopper Cosmotettix delector and some short-horned grasshoppers: Arphia pseudonietana (Red-Winged Grasshopper), Orphuella speciosa (Slantfaced Pasture Grasshopper), and Trachyrhachys kiowa (Kiowa Grasshopper). The caterpillars of the butterfly Satyrodes appalachia (Appalachian Brown) feed on sedges in habitats (upland savannas & woodlands) that are favored by Pennsylvania Sedge. Various birds eat the seeds of sedges; in thinly wooded upland habitats, these species include the Greater Prairie Chicken, Wild Turkey, immature Ruffed Grouse, various sparrows, and the Red-Eyed Towhee. The Prairie Vole feeds on sedges in such habitats as well.
Photographic Location: Wooded slopes in Vermillion County, Illinois.
Comments: This is one of the first sedges to bloom during the spring. Pennsylvania Sedge is very similar to Carex lucorum and Carex heliophila (Sun Sedge); these latter two species are sometimes considered different varieties of Pennsylvania Sedge (e.g., Carex pensylvanica distans & Carex pensylvanica digyna respectively). Compared to Pennsylvania Sedge, these species/varieties have longer perigynia (3.04.0 mm. in length). The perigyneal beaks of Carex lucorum are more slender and longer than those of Pennsylvania Sedge, while Sun Sedge has leaf blades that are more stiff and revolute (rolled). Another similar species, Carex communis, lacks the long stolons of Pennsylvania Sedge. Most of these species prefer similar habitats to Pennsylvania Sedge, although Sun Sedge is more common in the shorter prairies of the Great Plains states.