Description:
This
perennial rush forms a moderately dense to loose tuft of basal
leaves, from which one or more flowering culms develop. Withered
remnants of the preceding year's leaves are typically present. The
blades of basal leaves are up to 8" long and 7 mm. across; they are
pale
to medium green with stiffened tips that are hull-shaped. The blades of
basal
leaves are hairy toward their bases and along their margins; these
hairs are long, soft, and white. The culms are 4-16" long, light
green, terete, glabrous, and straight. Along each culm, there are 2-3
alternate leaves. The leaf sheaths are light to medium green, mostly
glabrous, longitudinally veined, and closed. At the throat of each
sheath (where it joins the blade), there is a tuft of hairs; these
hairs are long, soft, and white. The blades of alternate leaves are up
to 5" long and 6 mm. across; they are pale to medium green with
stiffened tips that are hull-shaped.
Each culm terminates in an umbel
of 3-12 flower clusters. The rays (floral stalks) of this umbel are
nearly zero to 3" long and erect to ascending; they are straight, light
green, and terete. The rays are divergent by less than 60º.
Individual flower clusters are 6-13 mm. long and 5-6 mm. across; they
are usually short-cylindric in shape, consisting of a dense cluster of
6-16 flowers. Each flower consists of 6 scaly tepals, 6 stamens, and a
pistil. The tepals are 2.5-4.0 mm. in length and lanceolate in shape;
they are initially light green to brownish yellow, becoming light to
dark brown with age. However, the margins of the tepals are
white-membranous. At the base of each flower or flower cluster, there
are one or more chaffy bractlets that are less than 3 mm. in length. At
the base of the inflorescence, there is a leafy bract up to 2" long,
resembling a small leaf blade. The blooming period occurs during mid-
to late spring, lasting about 1-1½ weeks. The flowers are
cross-pollinated
by the wind.
Afterwards, the ovaries
develop into seed capsules that
are a little shorter than the tepals. These capsules are
obovoid-globoid and somewhat 3-lobed longitudinally, terminating
abruptly into a very short beak. At maturity, each capsule splits open
into 3 sections from the top, releasing 3 seeds. These seeds are small
and light enough to be blown about by the wind. Individual seeds are
about 1.5 mm. in length (excluding their food appendages), broadly
ellipsoid in shape, and dark brown. Attached to one end of each seed,
there is a white food appendage about 0.5 mm. in length. The root
system is fibrous, occasionally forming clonal offsets.
Cultivation:
The preference is partial sun, dry-mesic conditions, and
soil
containing some clay, rocky material, or sand. Most growth and
development occurs during the cool weather of spring.
Range
& Habitat: The native Common
Wood Rush (
Luzula
multiflora)
is fairly common in southern
Illinois, occasional in NE Illinois, and uncommon or absent elsewhere
within the state. Habitats include upland areas of hilly woodlands,
edges of bluffs, areas along paths in upland woodlands, shaded
rocky cliffs and rocky ledges, sandy savannas, and sand prairies. This
rush is found in natural areas of moderate to high quality. Some
disturbance is probably beneficial if it removes excessive shade from
overhead canopy trees.
Faunal
Associations: Very little is known
about floral-faunal relationships for this species. Because the seeds
have food appendages, they are carried about by ants and possibly other
insects. These insects help to spread the seeds to new locations.
Photographic
Location: A sandy savanna at Indiana Dunes State Park in
NW Indiana.
Comments:
Common Wood Rush (
Luzula
multiflora) resembles a grass in its vegetative state, but
its seeds and
scaly tepals are similar to those of other species in the
Rush family (Juncaceae). It is also unusual in preferring upland
woodland habitats, as most species in the Rush family prefer habitats
that are more wet and sunny.
The taxonomy of the Wood Rush complex
involving several
Luzula
spp. has a history of instability. In the
past, Common Wood Rush was classified as a variety of a European
species, or
Luzula
campestris multiflora. This rush is also considered a
distinct species,
Luzula
multiflora,
but in the past it was lumped
together with another similar species,
Luzula echinata
(Hedgehog Wood Rush). As a result,
Luzula
multiflora and
Luzula
echinata are sometimes
confused. The latter species can be distinguished by the more divergent
rays of its umbels (exceeding 60º), which can be erect, ascending,
widely spreading, or declining. In addition, the flower
clusters of the latter species are more flattened (often more wide than
tall) and each of these clusters usually contain fewer flowers
(typically 3-8). Another species,
Luzula
bulbosa (Bulbous Wood Rush),
was also assigned to the Wood Rush complex, but it is
now considered distinct. This last species can be distinguished by the
small bulbous tubers of its root system and its seeds are usually
smaller in size (typically about 1.0 mm. in length, excluding the food
appendages). All of these species are native to Illinois and they can
be found in similar habitats.