Eragrostis mexicana |
Eragrostis trichodes |
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giant helleborine, Mexican love grass, Orcutt's lovegrass |
sand lovegrass |
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Habit | Plants annual; cespitose, without innovations. | Plants perennial; cespitose, with innovations, without rhizomes, not glandular. | ||||
Culms | 10-130 cm, erect, sometimes geniculate, glabrous, sometimes with a ring of glandular depressions below the nodes. |
30-120 (160) cm, erect, glabrous and non-glandular below the nodes. |
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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. |
sometimes villous along the margins, apices hairy, hairs to 5 mm; ligules 0.3-0.5 mm; blades 15-46(65) cm long, 1.5-8 mm wide, flat to involute, abaxial surfaces glabrous, adaxial surfaces scabridulous, sometimes also pilose on the basal 1/4, hairs to 4 mm. |
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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. |
30-80 cm long, 6-30 cm wide, oblong to ovoid, diffuse; primary branches 2-35 cm, diverging 20-90° from the rachises, naked basally; pulvini hairy or glabrous; pedicels 2-22 cm, diverging, capillary. |
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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. |
3-15 mm long, 1.5—3.6 mm wide, ovate to lanceolate, greenish-yellow with a reddish-purple tinge, with (2)4-18 florets; disarticulation acropetal, paleas 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. |
subequal, 1.8-4 mm, narrowly ovate to linear-lanceolate, membranous, apices acuminate; upper glumes as long as or longer than the basal lemmas; lemmas 2.2-3.5 mm, broadly ovate to lanceolate, membranous, strongly keeled, keels not glandular, lateral veins conspicuous, apices acute; paleas 1.8-2.8 mm, hyaline, narrower than the lemmas, keels ciliolate, apices obtuse to truncate; anthers 3, 1-1.6 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. |
0.8-1.3 mm, rectangular-prismatic, somewhat laterally compressed, with a wide, deep adaxial groove, faintly striate, opaque, dark reddish-brown. |
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2n | = 60. |
= 40. |
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Eragrostis mexicana |
Eragrostis trichodes |
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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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AL; AR; CO; IA; IL; IN; KS; LA; MI; MN; MO; MS; NE; NM; NY; OH; OK; SD; TN; TX; VA; WI; WY
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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 trichodes grows in sandy to gravelly prairies, open sandy woods, rocky slopes, and roadsides, at 100-2150 m, often in associations with Quercus marilandica, Q. stellata, Juniperus, and Redfieldia flexuosa. It is endemic to the contiguous United States, and is available commercially as an ornamental. Records from outside the primary range probably reflect introductions. (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. 93. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | E. trichodes var. pilifera, E. pilifera | |||||
Name authority | (Hornem.) Link | (Nutt.) Alph. Wood | ||||
Web links |
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