Description: This native
perennial grass is 1-3' tall, branching occasionally; it is erect to sprawling.
The slender culms are light green, terete, and glabrous. The blades of the
alternate leaves are up to 6" long and ½" across; they are linear, dull
light green, and hairless. Each leaf blade tapers at its base and it is either
flat or indented in the middle. The leaf sheaths are dull light green and
hairless. Each culm terminates in a panicle of spikelets up to 8" long and half
as much across. The branchlets of this panicle are slender, whitish green,
glabrous, slightly wiry (but otherwise straight), and stiff; they are spreading
to ascending, and sparsely produced. There are 5-10 appressed spikelets along
the upper half of each branchlet; the lower half is naked. On each branchlet,
these spikelets are arranged together in a row. Each spikelet is about 3 mm.
long and 1 mm. across, light green, oblongoid, and glabrous or sparsely
white-mealy; it consists of a single lemma and a single palea enclosing the
floret. There are no glumes. The margins and keel of the lemma are often finely
ciliate. The floret has 2 white anthers and 2 white plumose stigmas. The
blooming period occurs from mid-summer to early fall. Each floret develops a
single grain. The root system has scaly rhizomes and fibrous roots. This grass
occasionally forms vegetative colonies from its rhizomes; it also reproduces
sexually by its fertilized grains.
Cultivation: The preference is light shade to
partial sun, moist to mesic conditions, and fertile loamy soil with abundant
organic matter.
Range & Habitat:
White Grass is occasional to locally common throughout Illinois (see
Distribution
Map). Habitats include moist to mesic deciduous woodlands, woodland
openings, moist meadows in wooded areas, powerline clearances in wooded areas,
edges of woodland paths, partially shaded low-lying areas along lakes and
rivers, swamps, marshes, and seeps. This grass is usually found in moist
woodlands or partially shaded areas of wetlands. It tolerates, or even prefers,
low levels of disturbance in these areas.
Faunal Associations: The caterpillars of the
butterfly Enodia anthedon (Northern Pearly Eye) feed on the foliage of
White Grass. Aside from this, little is known about floral-faunal relationships
for this species.
Photographic
Location: A moist deciduous woodlands in Urbana,
Illinois.
Comments: White Grass is a
good example of the kinds of grasses that grow in wooded areas. Such grasses
usually have delicate thin-textured foliage and their panicles or racemes are
slender and lanky with small spikelets. As a general rule, they are not very
showy. White Grass is fairly easy to identify because its spikelets are
appressed together to form a single row along the upper half of each branchlet.
Each spikelet is single-flowered, oblongoid, and often ciliate along the
margins of its lemma. Each floret of White Grass produces only 2 anthers; this
is unusual, because most grasses produce 3 anthers per floret. Other Leersia
spp. in Illinois are found primarily in sunny wetlands and are less
delicate. One of them, Leersia oryzoides (Rice Cutgrass), is
exceptionally harsh with sawtooth margins along its leaf blades and stiff
bristly hairs everywhere else. The spikelets of these other Leersia spp.
are larger in size (4 mm. or more in length) than those of White
Grass.