Description:
This grass is a summer annual about ½-1½' tall, forming a small tuft of
leafy culms. These culms are erect to widely spreading and unbranched;
they are light green to reddish green, terete, slender, and glabrous.
There are 2-4
alternate leaves along the length of each culm; their blades
are ascending to widely spreading. The leaf blades are 2-4" long and
3-5 mm. across; they are light green or grayish green, flat, and
largely glabrous. The base of each blade is wider than the culm. At
regular intervals along the margins of each blade, there are minute
glandular droplets (may require 10x hand lens to see). The leaf sheaths
are light green to dull purple and longitudinally veined; each sheath
is slightly hairy above and glabrous below. At the junction of each
sheath and blade, there is a conspicuous tuft of fine white hairs.
Each
culm terminates in a somewhat airy panicle of spikelets that is 1½-4"
long and about one-half as much across; in outline, each panicle is
narrowly pyramidal to ovoid. The central axis and lateral branches of
each panicle are light green, slender, and glabrous. The
lateral branches are widely spreading to ascending, dividing into short
lateral branchlets that are divergent. At the tips of these branchlets,
there are elongated spikelets about 4-10 mm. long and 1.5-2 mm.
across. Immature spikelets are light grayish green to dark purple,
while mature spikelets become light tan.
Individual spikelets are narrowly oblongoid and flattened in shape,
consisting of 5-18 florets and their overlapping lemmas (scales with
florets) that are arranged in 2 columnar ranks. Each spikelet is
slightly less wide at the top than the bottom. At the bottom of each
spikelet, there is a pair of glumes (scales without florets).
Individual glumes are about 1.5 mm. long, lanceolate in shape,
glabrous, and folded along their keels; one glume is slightly longer
than the other. Located above the glumes, the individual lemmas are
1.5-2.0 mm. in length. The lemmas are lanceolate-ovate in
shape, glabrous, 3-veined, and folded along their keels. Hidden behind
each lemma, there is a single floret and a membranous palea. The
anthers of each floret are about 0.2 mm. long.
The blooming period occurs from mid-summer to early fall. The
florets are cross-pollinated by the wind. Fertile florets are replaced
by tiny ovoid grains (up to 1 mm. long); the latter are small enough to
be blown about by the wind. The shallow root system is fibrous. At
favorable sites, this grass often forms colonies by reseeding itself.
Cultivation:
The preference is full sun, mesic to dry conditions, and barren soil
containing gravel or sand. Most growth and development occurs during
the summer. Because of its C4 metabolism, this weedy grass is able to
tolerate hot dry conditions.
Range
& Habitat:
The non-native
Lesser Love Grass is occasional to locally common throughout Illinois;
it is probably more common than official records indicate. This
grass was accidentally
introduced into the United
States from Eurasia.
Habitats include fields, sandy or gravelly areas along railroads,
roadsides, cracks in urban sidewalks, areas along paths, and barren
waste areas. Open areas with a history of disturbance and scant ground
vegetation are preferred.
Faunal
Associations: The following
information applies to Love grasses (
Eragrostis spp.) in
general. These
grasses are one group of host plants for the caterpillars of
Poanes
hobomok (Hobomok Skipper) and
Poanes zabulon
(Zabulon Skipper). Because
they often grow in dry open areas where grasshoppers occur,
occasionally their foliage is eaten by such species as
Melanoplus
sanguinipes (Migratory Grasshopper) and
Orphulella speciosa
(Slant-faced
Pasture Grasshopper). Other insect feeders include the aphid
Colopha
ulmicola and the flea beetle
Chaetocnema pulicaria
(Thomas, 1877; Clark
et al., 2004). Most species of love grass, including Lesser Love Grass,
provide poor forage for cattle and other mammalian herbivores, although
they will be eaten when little else is available.
Photographic
Location: Along a railroad in Urbana, Illinois.
Comments:
Another scientific name of this grass species is
Eragrostis
poaeoides. Love Grasses (
Eragrostis spp.)
are often difficult to
identify. One key characteristic of Lesser Love Grass is the presence
of glandular droplets along the margins of its leaf blades. It shares
this characteristic with another introduced species, Stinkgrass
(
Eragrostis cilianensis),
which is similar in appearance. Stinkgrass
resembles a large version of Lesser Love Grass with an inflorescence
that is more compact and cluttered. It usually has more lemmas per
spikelet (10-40) and its lemmas are longer (2.0-2.5 mm. in length).
Stinkgrass usually has glandular droplets along the margins of its
spikelets, while Lesser Love Grass usually lacks this characteristic.
Both of these species belong to a group of Love Grasses with the
following two characteristics: 1) their lemmas disarticulate
individually from the spikelets, while their paleas are often
persistent, and 2) disarticulation of the lemmas proceeds from the
bottom of a
panicle of spikelets to the top. More more information, see Efloras,
Flora of Pakistan (www.efloras.org).