This sedge is a herbaceous perennial, forming loose tufts of leafy
culms about 1-2' tall (rarely up to 3' tall). Both fertile and sterile
culms are present. The culms are 3-angled, hard rather than spongy,
medium green, hairless, and unbranched. The fertile culms are
rough-textured along the angles below the inflorescence, otherwise they
are smooth. There are about 3 alternate leaves along the lower
one-fourth of each fertile culm, while the remainder of the culm is
naked. The blades of these leaves are ascending, arching, or widely
spreading; they are 2-3 mm. across (rarely wider), 4-8" long, medium
green, hairless, and longitudinally furrowed. The
sheaths are relatively tight. The outer 2 sides of each leaf sheath are
light green and hairless, while the inner inside is membranous and
concave at its mouth. Each fertile culm terminates in an inflorescence
(typically about 2-3" long), consisting of a terminal staminate
spikelet (rarely 2 staminate spikelets), 2 pistillate spikelets (less
often 3 pistillate spikelets), and one or more leafy bracts. Sometimes
staminate florets are located at the apex of non-terminal spikelets,
otherwise their florets are pistillate. The staminate spikelet is ½–1½"
long, very narrow, erect, and brown. The pistillate spikelets are ½–1"
long, 4-5 mm. across, narrowly cylindrical, erect to ascending, and
sessile (or nearly so); these spikelets do not usually overlap each
other along the rachis (central stalk) of the inflorescence. The
perigynia of the pistillate spikelets are about 2.0 mm. long and 1.5
mm. across; they are orbicular-ovate to orbicular-obovate in shape,
plano-convex, slightly inflated, hairless, and whitish to yellowish
green while immature. The
pistillate scales are about 2.5 mm. long, 0.5 mm. across, and
linear-lanceolate to lanceolate in shape; they have light green central
veins and reddish brown margins, otherwise they are
translucent-membranous. At the base of the lowest pistillate spikelet,
a leafy bract that is about 1½–3½" long and 1-2 mm. across. Other leafy
bracts are less than 1" long and 1 mm. across, or they are absent.
The blooming period occurs during late spring for about 1-2 weeks. The
florets are cross-pollinated by the wind. The mature achenes are about
0.5–1.0 mm. long,
flattened-obovate in shape, rounded above, and obtusely tapered below.
The root system is fibrous and rhizomatous.
preference is full sun, wet to moist conditions, and sandy soil.
Standing water is readily tolerated if it is seasonal or temporary.
The native Hayden's Sedge is occasional
in NE Illinois,
while in the rest of the state it is rare or absent (see Distribution
). There is some evidence that its abundance has been
declining as a
result of drainage activities and various kinds of development
(eFloras, www.efloras.org; access date 5-21-15). This
sedge has been found in a variety of sunny wetland habitats, including
wet sand prairies, sedge meadows, grassy bogs, grassy fens, sandy
floodplains of rivers, edges of sandy marshes, and sandy ditches along
grassy paths in natural areas. Hayden's Sedge is found in higher
quality wetland habitats.
Many insects feed
on the foliage, seeds, and other parts of wetland sedges (Carex spp.
These species include leaf beetles (Plateumaris
larvae of leaf-miner flies (Cerodontha
larvae of a rust fly (Loxocera
), seed bugs (Cymus
plant bugs (Mimoceps
), a stink bug (Eurygaster alternata
other aphids, sedge grasshoppers (Stethophyma
), larvae of sawflies
larvae of skippers
larvae of such moths as Ctenucha
(Virginia Ctenucha) and Hypocoena
(Tufted Sedge Moth), and
larvae of a butterfly, Satyrodes
(Eyed Brown); see Clark
et al. (2004), Vaurie (1983), Majka et al. (2007), Spencer &
Steyskal (1986), Marshall (2006), Hoffman (1996), Knight (1941), Lattin
(1964), Blackman & Eastop (2013), Capinera et al. (2004), Smith
(2006), Bouseman et al. (2006), and Panzer (2006). Among vertebrate
animals, the seeds and spikelets of wetland sedges are eaten by ducks,
rails, and other birds (see the Bird Table
Wetlands with sedges also
provide important summer or migratory habitat for many birds. Muskrats
eat the culms, roots, and sprouts of wetland sedges, while White-tailed
Deer and Elk browse on the foliage sparingly. There is some evidence
that White-tailed Deer spread the seeds of sedges in their droppings
(Myers et al., 2004).
A sandy ditch along a
grassy path at the
Iroquois County Conservation Area in Illinois.
This is an attractive wetland sedge with erect culms and brownish to
reddish green spikelets. While Hayden's Sedge (Carex haydenii
compared to Tussock Sedge (Carex
) and other species in the
Tussock Sedge group, it is actually quite distinct. Hayden's Sedge is
smaller in size and the scales of its pistillate spikelets are longer
than the perigynia. In contrast, Tussock Sedge and other species in its
group are usually much larger in size and the scales of their
pistillate spikelets are the same length or shorter than the perigynia.
In addition, the tips of the pistillate scales for Hayden's Sedge are
more acute than those of Tussock Sedge and other species in its group,
and Hayden's Sedge usually has fewer staminate and pistillate spikelets
in its inflorescence.