For this perennial sedge, an infertile shoot consists of
a small tuft of ascending to arching basal leaves about ¾-1½'
tall, while a fertile shoot consists of a flowering leafy culm about
1-2' tall. Each culm is light green, 3-angled, and smooth to slightly
rough-textured (scabrous). Initially the culm is more or less erect,
but with the development of the inflorescence, it may lean sideways.
About 2-3 alternate leaves are located along the lower one-third of the
culm (not including any scale-like leaves at the bottom); their blades
are ascending to widely spreading. The leaf blades are 4-10" long and
2-6 mm. across; they are light green, glabrous, and often
longitudinally grooved. The basal leaves have characteristics that are
similar to the alternate leaves.
Each culm terminates in an
inflorescence with 1-3 sessile floral spikes and 2-8 floral spikes on
ascending to erect peduncles. The peduncles are 1-6" in length; they
are stiff, straight, and glabrous (or nearly so). Each spike consists
of a relatively broad obconic cluster of 8-20 spikelets. The spikelets
in each cluster are ascending to erect. Each spikelet is ½-1" long,
narrowly oblong in shape, and flattened, consisting of 5-18 perfect
florets and their scales. In each spikelet, the floral scales are
arranged in two columnar ranks; they are overlapping
and ascending. Individual scales are 2.5-3.5 mm. in length,
ovate in shape,
glabrous, and sharply folded along their keels. The lateral sides of
each scale have several fine veins. Each scale terminates in a short
narrow tip up to 1.0 mm. in length (it is mucronate). At the bottom of
each inflorescence, there are 3-6 leafy bracts of variable length
(1-8" long); they are erect to ascending. These bracts resemble
the leaf blades. The blooming period occurs during late summer to early
fall. The florets are wind-pollinated. Shortly afterwards, fertile
florets are replaced by achenes about 2.5-3.0 mm. long and 1.0 mm.
across; these achenes are oblongoid in shape, slightly flattened,
bluntly 3-angled, and hairless. At maturity, the achenes are light
brown. The root system is fibrous and rhizomatous.
The preference is full sun, dry-mesic conditions, and sandy soil.
Because of its C4 metabolism, this sedge is slow to develop during the
growing season, although it is resistant to summer heat and drought.
The native Midland Sand Sedge is
uncommon in northern Illinois, and rare or absent elsewhere in the
state (see Distribution
). Habitats consist of upland sand prairies,
stabilized sand dunes, upland sandy savannas, sandy areas along rivers,
and sandy fields. Occasional wildfires and other kinds of disturbance
are beneficial if they reduce competition from woody vegetation.
Larvae of Diploschizia impigritella
(Flatsedge Borer Moth) bore into the stems and leaf bases of Cyperus
Other insect feeders include the polyphagous billbugs
(Vaurie, 1983). Among vertebrate animals,
cattle readily browse on the foliage of Cyperus spp.
(Georgia, 1913), while White-Tailed Deer usually ignore it. In the open
sandy habitats where this sedge occurs, such birds as the Wild Turkey,
Greater Prairie Chicken, and Tree Sparrow occasionally eat the seeds or
An oak savanna on a stabilized sand dune near
Lake Michigan at Indiana Dunes State Park in NW Indiana.
Midland Sand Sedge has received very little attention in the past. It
is believed to be a naturally occurring hybrid that is descended
and Cyperus schweinitzii
as it displays intermediate characteristics. All of these sedges prefer
similar sandy habitats and their ranges overlap. Midland Sand Sedge
differs from Cyperus
by having obconic-shaped spikes,
straight peduncles, and ascending leafy bracts; the latter sedge has
nearly spheroid spikelets, peduncles that have a tendency to bend, and
leafy bracts that are more widely spreading. Midland Sand Sedge differs
by having culms with a more smooth surface, a
more dense cluster of spikelets per spike, and spikelets that are more
flattened along the keels of their scales.