Eragrostis airoides |
Eragrostis hirsuta |
|
---|---|---|
darnel lovegrass |
bigtop lovegrass |
|
Habit | Plants perennial; cespitose, with innovations, without rhizomes, not glandular. | Plants perennial; cespitose, with innovations and hardened bases, without rhizomes, not glandular. |
Culms | 30-110 cm, erect, glabrous below the nodes. |
(30)45-100 cm, erect, glabrous below the nodes. |
Sheaths | glabrous or pilose, hairs to 5 mm; ligules 0.1-0.2 mm; blades 8-22 mm long, (1)2-4(5) mm wide, flat to folded, glabrous abaxially, scabridulous adaxially. |
rarely glabrous, apices and distal margins usually hairy, sometimes also densely hairy basally, dorsally, and on the collars, hairs to 6 mm, papillose-based; ligules 0.2-0.4 mm; blades 25-60 cm long, 3-8(11) mm wide, flat to loosely involute, usually glabrous, adaxial surfaces sometimes hairy basally. |
Panicles | 18-70 cm long, 3-25 cm wide, diffuse, ovate; primary branches 4-20 cm, appressed or diverging 10-70° from the rachises, naked basally; pulvini glabrous; pedicels 2.4-11 mm, divergent. |
25-85 cm long, 15-40 cm wide, broadly ovate, open; primary branches mostly 4-35(45) cm, diverging 20-90° from the rachises, capillary; pulvini glabrous or hairy; pedicels 2-28 mm, divergent. |
Spikelets | 1.3-2 mm long, 0.8-1.8 mm wide, ovate to lanceolate, plumbeous, with 1-3 florets; disarticulation acropetal, in the rachilla below the florets, glumes deciduous; rachilla prolonged above the terminal floret. |
2-4(5) mm long, 1-1.7 mm wide, lanceolate, greenish with purplish tinges, with 2-6 florets; disarticulation acropetal, paleas persistent. |
Glumes | lanceolate to ovate, membranous; lower glumes 0.8-1 mm; upper glumes 1.1-1.4 mm; lemmas 0.8-1.2 mm, ovate, membranous, plumbeous, keels and lateral veins inconspicuous, apices obtuse; paleas 0.8-1.2 mm, membranous, bases not projecting beyond the lemmas, apices obtuse; anthers 3, 0.3-0.5 mm, purplish. |
lanceolate, hyaline to membranous; lower glumes 1.1-2 mm; upper glumes 1.5-2.8 mm, apices acuminate to acute; lemmas 1.6-2.4 mm, ovate, membranous, hyaline near the margins, lateral veins inconspicuous, apices acute; paleas 1.2-2.2 mm, hyaline, bases not projecting beyond the lemmas, apices acute to obtuse; anthers 3, 0.3-0.8 mm, purplish. |
Caryopses | 0.4-0.5 mm, ovoid, reticulate, reddish-brown. |
0.8-1 mm, rectangular-prismatic, somewhat laterally compressed, with or without a well-developed adaxial groove, striate, opaque, reddish-brown. |
Comm | .). |
|
2n | = 36 (Davidse, pers. |
= 100. |
Eragrostis airoides |
Eragrostis hirsuta |
|
Distribution |
TX |
AL; AR; DE; FL; GA; IL; KY; LA; MA; MD; MO; MS; NC; NJ; OH; OK; SC; TN; TX; VA; WV
|
Discussion | Eragrostis airoides is a South American species that, in the Flora region, is known only from roadsides and disturbed sites in Brazos County, Texas. It is an enigmatic species, often treated as Sporobolus brasiliensis (Raddi) Hack., which it resembles in its chromosome base number of x = 9 and caryopsis morphology, but its frequent possession of spikelets with more than 1 floret and its mode of spikelet disarticulation argue for its retention in Eragrostis. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eragrostis hirsuta grows in sandy clay loams on the coastal plain and along roadsides, at 0-150 m, usually in association with Pinus palustris and Quercus. Its range extends from the southeastern United States through eastern Mexico to Guatemala and Belize. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 25, p. 103. | FNA vol. 25, p. 95. |
Parent taxa | Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Eragrostis | Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Eragrostis |
Sibling taxa | ||
Synonyms | E. hirsuta var. laevivaginata | |
Name authority | Nees | (Michx.) Nees |
Web links |