Contains 22 accepted taxa overall.
Characteristics
Classification
Citation
ARISTIDA Linnaeus, Sp. Pl. 82. 1753.
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TYPE: Aristida adscensionis Linnaeus
Species
| Scientific Name | Common Name | Herbarium Specimens | Status | Photos |
|---|---|---|---|---|
| Aristida condensata | BIG THREEAWN; PIEDMONT THREEAWN | Native | ||
| Aristida dichotoma var. curtissii | CURTISS' THREEAWN | Native | ||
| Aristida dichotoma var. dichotoma | CHURCHMOUSE THREEAWN | Native FACU (NWPL) | ||
| Aristida floridana | KEY WEST THREEAWN | Native | ||
| Aristida gyrans | CORKSCREW THREEAWN | Native | ||
| Aristida lanosa | WOOLLYSHEATH THREEAWN | Native | ||
| Aristida longespica var. geniculata | RED THREEAWN | Native | ||
| Aristida longespica var. longespica | SLIMSPIKE THREEAWN | Native FACU (NWPL) | ||
| Aristida mohrii | MOHR'S THREEAWN | Native | ||
| Aristida oligantha | PRAIRIE THREEAWN | Native | ||
| Aristida palustris | LONGLEAF THREEAWN | Native OBL (NWPL) OBL (DEP) | ||
| Aristida patula | TALL THREEAWN | Native FAC (NWPL) | ||
| Aristida purpurascens var. purpurascens | ARROWFEATHER THREEAWN | Native UPL (NWPL) FACW (DEP) | ||
| Aristida purpurascens var. tenuispica | HILLSBORO THREEAWN | Native FAC (NWPL) FAC (DEP) | ||
| Aristida purpurascens var. virgata | ARROWFEATHER THREEAWN | Native FACW (NWPL) FAC (DEP) | ||
| Aristida purpurea | PURPLE THREEAWN | Not Native | ||
| Aristida ramosissima | S-CURVE THREEAWN; CHASE THREEAWN | Native | ||
| Aristida rhizomophora | FLORIDA THREEAWN | Native FACW (NWPL) FAC (DEP) | ||
| Aristida simpliciflora | SOUTHERN THREEAWN; CHAPMAN THREEAWN | Native FAC (NWPL) | ||
| Aristida spiciformis | BOTTLEBRUSH THREEAWN | Native FAC (NWPL) FAC (DEP) | ||
| Aristida stricta | WIREGRASS | Native FAC (NWPL) FAC (DEP) | ||
| Aristida tuberculosa | SEASIDE THREEAWN | Native |
Identification Key
1. Lower glume with 3-7 veins
2
1. Lower glume with 1-2(3) veins
3
2. Upper glume awn (7)11-20(24) mm long; lemma central and lateral awns subequal, (8)12-65(70) mm long
2. Upper glume awn 3-7 mm long; lemma lateral awns 1-4 mm long, the central awn 12-25 mm long
3. Lemma central awn spirally coiled at base
4
3. Lemma central awn straight to curved (if coiled, then awns joined to form a column)
4. Glumes unequal, lower 5-8(10) mm long, upper 7-13 mm long; lemmas smooth to scabridulous, 6-11 mm long
4. Glumes subequal, lower 3-6 mm long, upper 4-7 mm long; lemmas sparsely appressed-pubescent, 3-8 mm long
5. Lemma lateral awns absent or to 1 mm long; inflorescence 5-25 cm wide
5. Lemma lateral awns 3- mm long (if absent, inflorescence 1-6 cm wide) <1/2 as long as the central awn
6
6. Inflorescence nodes and usually leaf sheaths lanose-floccose
6. Inflorescence nodes and leaf sheaths glabrous to sparsely pilose
7
7. Leaf blade tightly involute, pilose on outer surface and often the region near ligule; generally flowering only after fire
7. Leaf blade flat, folded, or involute and glabrate; flowering without fire or after fire
8
8. Inflorescence densely spiciform, branches appressed, spikelets congested; upper glumes awned, the awns 10-12 mm long; lemmas terminating in a beak 7-30 mm long
8. Inflorescence loosely racemiform, paniculiform, or racemiform, branches spreading to appressed, spikelets relatively well spaced; upper glumes unawned or with an awn to 6 mm long; lemmas not beaked or with a beak less than 7 mm long
9
9. Lemma awns clearly jointed with the lemma blade, the awns disarticulating
9. Lemma awns confluent with the lemma blade
10
10. Inflorescence 15-25 cm wide, the branches base with pulvini, the branches mostly widely spreading to drooping
10. Inflorescence 2-12 cm wide, the branches without pulvini (rarely present in A. purpurea), appressed, ascending, to spreading or drooping
11
11. Rhizomatous and densely cespitose; basal leaf sheaths becoming fibrous with age
11. Cespitose, without rhizomes; basal leaf sheaths mostly remaining intact or flaking
12
12. Inflorescence unbranched, the nodes with a single spikelet
12. Inflorescence nodes with branches or multiple spikelets
13
13. Glumes unequal, lower 4-12 mm long, upper 7-25 mm long
14
13. Glumes subequal or the lower longer, 2-11 mm long
15
14. Lower glume 6-9(11) mm long, upper glume 9-12 mm long; lemmas 5-7 mm long, awns 8-15 mm long; callus 1-2 mm long
14. Lower glume 4-12 mm long, upper glume 7-25 mm long; lemmas 6-16 mm long, awns (8)15-140 mm long; callus 0.5-1.8 mm long
15. Lower glume strongly 2-keeled, (7.5)9-13 mm long; central awns 15-40 mm long
15. Lower glume 1-keeled (if 2-keeled, 5-10 mm long); central awns 8-25(27) mm long
16
16. Lemma awns divergent to reflexed, contorted at base, central awns ca. twice as thick as lateral awns, divergent to arcuate-reflexed
16. Lemma awns mostly erect to ascending, not contorted at base, central and lateral subequal in thickness or central ca. twice as thick but not contorted
17
17. Culms 3-6 mm wide at base; primary inflorescence branches 4-20 cm long; lower glume 1-veined; callus 1-2 mm long
17. Culms 1-4 mm wide at base; primary inflorescence branches 1-5 cm long; lower glume with 1-2 veins; callus 0.4-0.8 mm long
18
18. Annual; internodes mostly longer than the leaf sheaths; ligules ca. 0.5 mm long; leaf blades 5-14 cm long, 1-2 mm wide; inflorescence 6-22 cm long
19
18. Perennial; internodes mostly shorter than the leaf sheaths; ligules ca. 0.2 mm long; leaf blades 10-25 cm long, 1-3 mm wide; inflorescence (15)20-55 cm long
20
19. Lemma central awns 8-27 mm long, lateral awns (1)6-18 mm long
19. Lemma central awns 1-10(14) mm long, lateral awns absent or to 5(8) mm long
20. Central awns divaricate to reflexed, ca. twice as thick at the base as the lateral awns
20. Central and lateral awns divergent, subequal in thickness at the base
21
21. Leaf blades 1-3 mm wide, often curling; glumes unequal, lower 6-10 mm long, upper 5-8 mm long; lemma awns straight or only slightly contorted at the base;
21. Leaf blades 1(-1.5) mm wide, usually not curling; glumes subequal, 8-9 mm long; lemma awns spirally contorted at the base;
Genus Synonyms
| Synonym | Full Citation | Basionym | Type |
|---|---|---|---|
| Aristopsis | Aristopsis Catasús Guerra, Folia Geobot. Phytotax. 16: 439. 1981. | TYPE: Aristopsis bissei Catasús Guerra | |
| Arthratherum | Arthratherum Palisot de Beauvois, Ess. Agrostogr. 32, 152, pl. 8(8-9). 1812. | TYPE: Arthratherum hygrometricum (R. Brown) Palisot de Beauvois (Aristida hygrometrica R. Brown) Lectotypified by Niles & Chase, Contr. U.S. Natl. Herb. 24: 166. 1925. | |
| Chaetaria | Chaetaria Palisot de Beauvois, Ess. Agrostogr. 30, 158, pl. 8(5-6). 1812. | TYPE: Chaetaria stricta (Michaux) Palisot de Beauvois (Aristida stricta Michaux) Lectotypified by Hitchcock, U.S.D.A. Bull. (1915-1923) 772: 163. 1920. | |
| Curtopogon | Curtopogon Palisot de Beauvois, Ess. Agrostogr. 32, 159, pl. 8(7). 1812. | TYPE: Curtopogon dichotomus (Michaux) Palisot de Beauvois (Aristida dichotoma Michaux) | |
| Kielboul | Kielboul Adanson, Fam. Pl. 2: 31, 539. 1763. | TYPE: = Aristida Linnaeus 1753. | |
| Moulinsia | Moulinsia Rafinesque, Bull. Bot. (Geneva) 1: 221. 1830, non Cambessedes 1829. | TYPE: Aristida lanosa Muhlenberg ex Elliott | |
| Stipagrostis | Stipagrostis C. Nees von Esenbeck, Linnaea 7: 290. 1832. | TYPE: Stipagrostis capensis C. Nees von Esenbeck | |
| Streptachne | Streptachne R. Brown, Prodr. 174. 1810. | TYPE: Streptachne stipoides R. Brown | |
| Trixostis | Trixostis Rafinesque, Bull. Bot. (Geneva) 1: 221. 1830. | TYPE: Aristida gracilis Elliott |