Eragrostis mexicana |
Eragrostis silveana |
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giant helleborine, Mexican love grass, Orcutt's lovegrass |
Silveus' lovegrass |
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Habit | Plants annual; cespitose, without innovations. | Plants perennial; cespitose, with innovations and short, knotty rhizomes less than 4 mm thick. | ||||
Culms | 10-130 cm, erect, sometimes geniculate, glabrous, sometimes with a ring of glandular depressions below the nodes. |
45-60 cm, erect, often glandular below the nodes, sometimes viscid. |
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Sheaths | sometimes with glandular pits, pilose near the apices and on the collars, hairs to 4 mm, papillose-based; ligules 0.2-0.5 mm, ciliate; blades 5-25 cm long, 2-7(9) mm wide, flat, abaxial surfaces glabrous, adaxial surfaces scabridulous, occasionally pubescent near the base. |
often viscid, sometimes sparsely pilose, hairy at the apices, hairs to 6 mm; ligules 0.2-0.3 mm; blades 8-25 cm long, 2-4 mm wide, flat to involute, glabrous, sometimes viscid. |
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Panicles | (5)10-40 cm long, (2)4-18 cm wide, ovate, rachises angled and channeled; primary branches 3-12(15) cm, solitary to whorled, appressed or diverging to 80° from the rachises; secondary branches somewhat appressed; pulvini glabrous; pedicels 1-6(7) mm, almost appressed to narrowly divergent, stiff. |
20-35(42) cm long, 10-22 cm wide, broadly ovate, open, bases included in the uppermost leaf sheaths; primary branches 5-14 cm, diverging 20-90° from the rachises, capillary, sometimes viscid, naked basally; pulvini hairy, hairs to 6 mm; pedicels (1)1.5-12 mm, diverging or appressed. |
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Spikelets | (4)5-10(11) mm long, 0.7-2.4 mm wide, ovate to linear-lanceolate, gray-green to purplish, with 5-11(15) florets; disarticulation acropetal. |
(2.5)3-4.8 mm long, 0.9-1.4 mm wide, linear-lanceolate, reddish-purple, with 4-9 florets; disarticulation basipetal, glumes persistent. |
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Glumes | subequal, 0.7-2(2.3) mm, ovate to lanceolate, membranous; lemmas 1.2-2.4 mm, ovate, membranous, glabrous or with a few hairs, gray-green, lateral veins evident, often greenish, apices acute; paleas 1-2.2 mm, hyaline, keels scabrous, apices obtuse to truncate; anthers 3, 0.2-0.5 mm, purplish. |
lanceolate, membranous; lower glumes 0.9-1.2 mm; upper glumes 1-1.3 mm; lemmas 1.1-1.4 mm, ovate to lanceolate, membranous, 3-veined, apices acute; paleas 1-1.4 mm, hyaline, not wider than the lemmas, apices obtuse; anthers 3, 0.2-0.3 mm, purplish. |
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Caryopses | 0.5-0.8(1) mm, ovoid to rectangular-prismatic, laterally compressed, shallowly to deeply grooved on the adaxial surface, striate, reddish-brown, distal 2/3 opaque. |
0.5-0.6 mm, ellipsoid, terete in cross section, neither ridged nor grooved, faintly striate, reddish-brown. |
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2n | = 60. |
= unknown. |
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Eragrostis mexicana |
Eragrostis silveana |
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Distribution |
AZ; CA; CO; DE; FL; IA; ID; IL; IN; MA; MD; ME; ND; NM; NV; OR; SC; TX; UT; WA; WI; BC; ON
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TX |
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Discussion | Eragrostis mexicana grows along roadsides, near cultivated fields, and in disturbed open areas, at 100-3000 m. It is native to the Americas, its native range extending from the southwestern United States through Mexico, Central and northern South America, to Argentina. Within the Flora region, it has been introduced beyond its native range, often becoming an established part of the flora. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eragrostis silveana grows in various open habitats, from sandy prairies to clay loam flats, near roadsides, railroads, and fields at 0-100 m. Its range is limited to the coastal plain of Texas and northern Mexico. Morphologically, E. silveana is somewhat intermediate between E. spectabilis and E. curtipedicellata, and grows where the distribution of these two species overlaps. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 25, p. 78. | FNA vol. 25, p. 91. | ||||
Parent taxa | Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Eragrostis | Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Eragrostis | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Name authority | (Hornem.) Link | Swallen | ||||
Web links |
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