Part 7 - UNC Herbarium

POACEAE 882
Eragrostis Wolf 1776 (Lovegrass)
A genus of about 350 species of temperate and tropical areas. References: Peterson in FNA (2003a); Koch (1978); Peterson &
Harvey (in prep.)=Z. Key adapted from Peterson & Harvey (in prep.).
1 Plants cespitose or rhizomatous perennials, with innovations near the base, and with or without buds in the basal sheaths.
2 Plants with short, knotty, thick rhizomes; florets articulating whole .............................................................E. spectabilis
2 Plants without short or thick rhizomes; florets usually disarticulating.
3 Caryopsis with a deep to shallow groove along the adaxial surface.
4 Caryopsis dorso-ventrally compressed, flattened parallel to the side of the embryo, translucent, light brownish
........................................................................................................................................................... E. curvula
4 Caryopsis laterally compressed, flattened on the side perpendicular to the embryo, or cylindric, opaque
(rarely translucent), usually reddish brown.
5 Lateral veins of the lemmas conspicuous, often greenish, the lemmas strongly keeled ...........E. trichodes
5 Lateral veins of the lemmas inconspicuous and hardly evident, the lemmas sometimes weakly keeled.
6 Lemmas 1.2-1.8 mm long; culms 30-70 cm tall ...................................................................E. lugens
6 Lemmas 1.6-3.0 mm long; culms (30-) 40-110 (-120) cm tall.
7 Spikelets 2-6-flowered, greenish with purple tinges; leaf blades 3-8 (-11) mm wide, 25-60 cm
long; sheaths often densely papillose-hirsute............................................................... E. hirsuta
7 Spikelets (3-) 5-12-flowered, olive green to lead gray; leaf blades 1-3.8 mm wide, (4-) 10-35
cm long; sheaths never papillose-hirsute ............................................................... E. intermedia
3 Caryopsis not grooved on the adaxial surface.
8 Stamens 3.
9 Spikelets 4-8.2 (-10) mm long.................................................................................................... E. curvula
9 Spikelets 2-4.5 (-5) mm long.
10 Leaf blades 25-60 cm long, 3-8 (-11) mm wide; lemmas 1.6-2.4 mm long; spikelets 1.0-1.7 mm
wide..................................................................................................................................... E. hirsuta
10 Leaf blades (4-) 8-22 cm long, 1-3.5 mm wide; lemmas 1.2-1.8 mm long; spikelets 0.5-1.0 (-1.3)
mm wide ..............................................................................................................................E. lugens
8 Stamens 2.
11 Panicle 15-45 cm wide, open, diffuse, broadly ovate to obovate in outline, the panicle branches
capillary; pedicels 0.5-35 (-50) mm long, longer than or shorter than the spikelets.
12 Spikelets with widely spreading pedicels, the lower pedicels all generally longer than the spikelets;
disarticulation of the lemmas only, the paleas persistent..................................................... E. elliottii
12 Spikelets with appressed pedicels, lower pedicels of each branch shorter than the spikelets;
disarticulation usually of the whole floret ..........................................................................E. refracta
11 Panicle (1-) 2-17 (-20) cm wide, contracted to open, narrowly ovate to oblong in outline;, the panicle
branches stiffly spreading; pedicels (0-) 0.3-6 mm long, always shorter than the spikelets.
13 Spikelets 0.7-2.4 mm wide; glumes 0.3-2.2 mm long; lemma 1.5-2.5 mm long, the apex acute
(sometimes acuminate).................................................................................................... E. bahiensis
13 Spikelets 2.4-5 mm wide; glumes 1.4-4 mm long; lemma 2-6 mm long, the apex acuminate to
attenuate ................................................................................................E. secundiflora var. oxylepis
1 Plants cespitose, geniculate or mat-forming annuals, lacking innovations or buds in the lower sheaths.
14 Paleas prominently ciliate-pectinate on the keels, the hairs 0.1-0.8 mm long.
15 Panicles contracted, narrow, spike-like, usually < 1.5 cm wide ............................................... E. ciliaris var. ciliaris
15 Panicles open, cylindrical to narrowly ovate, usually 1-8 cm wide.
16 Spikelets (1.0-) 1.5-3.5 mm long, 0.9-1.4 mm wide, 4-12-flowered; lemmas 0.7-1.1 mm long, membranous,
the apex truncate to obtuse ................................................................................................................E. amabilis
16 Spikelets 5-12 (-18) mm long, 1.4-2.4 mm wide, 12-42-flowered; lemmas (1.3-) 1.5-2.0 mm long,
chartaceous, the apex acute .............................................................................................................. E. cumingii
14 Paleas smooth to scaberulous on the keels, the hairs (if present) < 0.1 mm long.
17 Plants extensively stoloniferous, creeping and forming flat mats; inflorescences 1-3.5 cm long; culms (2-) 5-12 (-
20) cm tall on the erect portions............................................................................................................. E. hypnoides
17 Plants not stoloniferous (sometimes creeping and forming flat mats); inflorescences 3-55 cm long; culms (2-) 6-
130 cm tall.
18 Ligules membranous, glabrous..........................................................................................................E. japonica
18 Ligules ciliate, with a row of tiny white hairs.
19 Caryopsis with a deep to shallow groove along the adaxial surface.
20 Spikelets (4-) 5-10 (-11) mm long, 5-11 (-15)-flowered; pedicels ascending, somewhat appressed
along the branches.
21 Spikelets ovate to oblong in outline, >1.4 mm wide; lower glume 1.2-2.3 mm long...................
......................................................................................................... E. mexicana ssp. mexicana
21 Spikelets linear to linear-lanceolate,