Narrow False Oat

This extremely polymorphic species is one of the most widespread of all flowering plants, being present in arctic and alpine parts of all continents except Africa. A large number of subspecies and varieties has been described, and these are only weakly correlated with geography. In spite of difficulties in applying infraspecific names, it seems unacceptable to include the very large range of forms present in China without subdivision under a single species name. Therefore subspecific names that have previously been applied are maintained here to indicate the main nodes of variation. However, variation is still very imperfectly understood, especially in the Himalayas, and it is not possible to place all specimens within the given subspecies descriptions.

An extremely variable grass, especially in panicle density and spikelet colour. In Europe and northern Asia it has been divided into a number of subspecies but material from our area is relatively uniform (except where it grades into Trisetum clarkei) and probably all referable to subsp. spicata. Very common at high altitudes. 3000-6000 m.

Perennial, densely tufted. Culms erect, 3–60 cm tall, 1–2 mm in diam., pubescent to tomentose especially below panicle, 1–3-noded. Leaf sheaths pubescent; leaf blades flat or rolled, 2–15 cm, 2–4 mm wide, densely to sparsely hairy on both surfaces or only abaxial surface, or glabrous, margins often setose; ligule 1–2 mm. Panicle spikelike, dense, linear to ovate or oblong in outline, lower part sometimes interrupted, 1.5–11 cm; branches short, appressed, pubescent to tomentose. Spikelets 4–9 mm, florets 2(or 3); rachilla hairs 1–1.5 mm; glumes subequal or slightly unequal, lower glume 4–8 mm, upper glume 5–9 mm, apex acuminate, occasionally briefly aristulate; lemmas lanceolate, 4–7 mm, scaberulous to pubescent, awned from upper 1/4–1/3, apex usually 2-denticulate, teeth often mucronate, occasionally subentire; awn 2–7 mm, weakly geniculate with loosely twisted column, or recurved at base, or almost straight; palea keels scaberulous. Anthers 0.7–1.3 mm. Fl. and fr. Jun–Sep.

Tufted perennial; culms 8-50 cm high, erect, puberulous with short reflexed hairs especially below the inflorescence. Leaf-blades 4-10 cm long, 1-3.5 mm wide, flat or somewhat convolute, villous to scaberulous. Panicle ovoid to cylindrical, dense but sometimes interrupted, the axis and branches puberulous, 1.5-7.5 cm long. Spikelets 2(-3)-flowered, 4-7.5 mm long excluding the awns; glumes subequal or unequal, elliptic, acute, the lower 1-3-nerved, 3.5-5 mm long, the upper 4-6.5 mm long; lemma elliptic, 4-5.5 mm long; awn 2.5-6.5 mm long, strongly recurved.

Gansu, Hebei, Heilongjiang, Hubei, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shanxi, Sichuan, Taiwan, Xinjiang, Xizang, Yunnan [Afghanistan, Bhutan, N India, Japan, Kazakhstan, Kyrgyzstan, Korea, Mongolia, Nepal, Pakistan, Russia, Tajikistan, Uzbekistan; SW Asia (Caucasus), Australia, Europe, North and South America].

Distribution; Pakistan (N.W.F.P., Gilgit & Kashmir); arctic and alpine regions of the northern hemisphere.

Fl. & Fr. Per.: July-August.

Grassy mountain slopes, alpine meadows, on glacial moraine, among bushes, montane forests; 1900–5600 m.

Trisetum montanum Vasey, Bull. Torrey Club 13: 118. 1886
Trisetum argenteum Scribn. Bull. U. S. Dep. Agr. Agrost. 11: 49. 1898. (Type from .Silverton,
Colorado. Shear 1214.) Not T. argenteum R. & S. 1817. Trisetum Shearii Scribn. Circ. U. S. Dep. Agr. Agrost. 30: 8. 1901 . (B.i.sed on T. argenteum Scribn.) Graphephorum Shearii Rydb. Bull. Torrey Club 32: 602. 1905. (Based on Trisetum Shearii
Scribn.) Trisetum canescens var. montanum Hitchc. Proc. Biol. Soc. Wash. 41: 160. 1928. (Based on
T. montanum Vasey.) Trisetum montanum var. pilosum Louis-Marie, Rhodora 30: 212. 1928. (Type from Caroles, New
Mexico, Standley 4536.) Trisetum montanum var. Shearii Louis-Marie, Rhodora 30: 213. 1928. (Based on T. Shearii
Scribn.)
Perennial; culms erect or decumbent at the base, glabrous, 50-100 cm. tall; sheaths glabrous or scabrous, or the lower sometimes more or less pilose; ligule truncate, erose-dentate, somewhat ciliate, 2-3 mm. long; blades flat, scabrous; panicle narrow, rather dense, pale or purplish, 10-15 cm. long, rarely longer, the axis scaberulous, the branches scabrous; spikelets 5-6 mm. long; glumes and lemmas thinner than in T. canescens, the second glume about 4 mm. long; lemmas scaberulous, the lower one about 5 mm. long; awn attached below the tip, spreading from near the base, not twisted, delicate, about 5 mm. long.
Type locality; Las Vegas, New Mexico (G. R. Vasey in 1881).
Distribution: Mountain meadows, gulches, and moist places on mountain slopes, altitude 2000-3000 meters, Colorado, Utah, and New Mexico.

Trisetum spicatum (L.) K. Riclit. PI. Eur. 1: 59. 1890
Aira spicala L. Sp. PI. 64. 1753. Not A. spicata L. op. cit. 63, this changed by Linnaeus, in the Aira subspicata L. Syst. Nat. ed. 10. 2: 873. 1759. (Based on A. spicata L. Sp. PI. 64. 1753, the
diagnosis copied.) Avena airoides Koeler, Descr. Gram. 298. 1802. (Based on Aira subspicata L.) ^I'cwa moi/ij Michx. Fl. Bor. Am. 1; 72. 1803. (Type from Canada.) Not ^. mo«/s Salisb. 1796,
nor A. mollis Koeler, 1802. Avena subspicata Clairv. Man. 17. 1811.
Trisetum subspicatum Beauv. Agrost. 88, 149, 180. 1812. (Based on Aira subspicata L.) Avena elongata H.B.K. Nov. Gen. & Sp. 1: 148. 1815. (Type from near Mexico City.) Avena lolucensis H.B.K. Nov. Gen. & Sp. 1: 148. 1815. (Type from Toluca, Mexico.) 7Melica iriflcrra Bigel. New Engl. Jour. Med. 5: 334. 1816. (Type from Mount Washington, New
Hampshire, Boolt.) Trisetaria airoides Baumg. Enum. Stirp. Transsilv. 3: 265. 1816. (Based on Avena airoides Koeler.) Trisetum airoides Beauv.; R. & S. Syst. Veg. 2: 666. 1817. (Based on Avena airoides Koeler.) Triselarium elongatum Poir. in Lam. Encyc. Suppl. 5: 366. 1817. (Based on Avena elongata H.B.K.) Trisetarium tolucense Poir. in Lam. Encyc. Suppl. 5: 366. 1817. (Based on Avena lolucensis H.B.K.) ^Avena squarrosa Schrank, Denks. Bot. Ges. Regensb. 1-: 7. 1818. (Type from Labrador.) Trisetum molle Kunth, R6v. Gram. 101. 1829. (Based on Avena mollis Michx.) Trisetum elongatum Kunth, Rev. Gram. 101. 1829. (Based on Avena elongata H.B.K.) Trisetum tolucense Kunth, R6v. Gram. 101. 1829. (Ba,sed on Avena lolucensis H.B.K.) Koeleria subspicata Reichenb. FI. Germ. Exc. 49. 1830. (Based on Aira subspicata L.) Trisetum labradoricum Steud. Syn. Gram. 228. 1854. (Type from Labrador.) Trisetum groenlandicitm Steud. ,Syn. Gram. 228. 1854. (Type from Greenland.) Trisetum subspicatum var. tnoHe A. Gray, Man. ed. 2. 572. 1856. (Based on Avena mollis Michx.) Rupestrina pubescens Prov. Fl. Can. 689. 1862. (Based on Avena mollis Michx.) Trisetum subspicatum var. laxius Lange, Consp. Fl. Groenl. 164. 1880. (Type from Greenland.) Trisetum subspicatum var. villosissimum Lange, Consp. Fl. Groenl. 164. 1880. (Type from Greenland.) Deyeuxia gracilis Foum. Mex. PI. Gram. 106. 1886. (Type from Mirador, Mexico, Liebmann 602.)
Not Trisetum gracile Boiss. 1845. Trisetum nivosum Foum. Mex. PI. Gram. 107. 1886. (Type from Nevado de Toluca, Mexico.) Trisetum interruptum Fourn. Mex. PI. Gram. 108. 1886. (Type from Mexico, Liebmann 605, 606,
607, being cited.) Not T. interruptum Buckl. 1863. Trisetum spicatum var. molle Beal, Grasses N. Am. 2: 377. 1896. (Based on Avena mollis Michx.) Trisetum Brittonii Nash, Bull. N. Y. Bot. Gard. 1: 437. 1900. (Type from Marquette, Michigan,
Britton in 1883.) Trisetum alaskanum Nash, Bull. N. Y. Bot. Gard. 2: 155. 1901. (Type from Skagway, Alaska,
Williams in 1899.) Trisetum Congdoni Scribn. & Merr. Bull. Torrey Club 29: 470. 1902. (Type from Mariposa Co.,
California, Congdon.) Trisetum americanum Gand. Bull. Soc. Bot. Fr. 49: 182. 1902. (Localities cited, Colorado, and
Idaho.) Trisetum majus Rydb. Bull. Colo. Agr. Exp. Sta. 100: 34. 1906. (Type from Pen Gulch, Colorado,
Vasey in 1884.) Avena spicata O. & B. Fedtsch. Acta Hort. Petrop. 28; 76. 1908. (Based on Aira spicata L.)
Not Avena spicata L. 1753. Trisetum spicatum var. pilosiglume Fernald, Rhodora 18: 195. 1916. (Type from Newfoundland,
Fernald, Wiegand, b" Bartram 4593.) Trisetum spicatum var. laxius O. Holmberg, .Skand. FI. 2: 175. 1926. (Based on T. subspicatum
var. laxius Lange.) Trisetum disjunctum Ix^uis-Marie. Rhodora 30: 218. 1928. (Based on T. interruptum Fourn. 1886,
not Buckl. 1863.) Trisetum humile Ixjuis-Marie, Rhodora 30: 244. 1928. (Based on Deyeuxia gracilis Fourn. Trisetum spicatum var. alaskanum Malte; Louis-Marie, Rhodora 30: 239. 1928. (Based on T.
alaskanum Na.sh.) Trisetum spicatum var. Brittonii Louis-Marie, Rhodora 30: 239. 1928. (Based on Trisetum Brittonii Nash.) Trisetum spicaturn Congdoni Hitchc. Proc. Biol. Soc. Wa.sh. 41: 160. 1928. (Based on Trisetum
Congdoni Scribn. & Merr.) Trisetum spicatum var. nivosum Louis-Marie, Rhodora 30: 239. 1928. (Based on T. nivosum
Fourn.) Triscliim spicalum var. villosissimum Louis-Marie, Rhodora 30: 239. 1928. (Based on T. sub-
spUalum var. villosissimum Lange.) ,^ ^ , „ , <
Trisetum albidum Sodiro, Revista CoL Nac. Vic. Rocaf. 12: 84, 86. 1930. (Type from Ecuador.) Trisetum gracile Sodiro, Revista Col. Nac. Vic. Rocaf. 12: 84, 85. 1930. (Type from Ecuador.) Not T. gracile Boiss. 1845.
Perennial; culms densely tufted, erect, glabrous to puberulent, 15-50 cm. tall; sheaths puberulent or, especially in the southern part of our range, glabrous; ligule truncate, erosedentate, 1-2 mm. long; blades flat or loosely involute, usually more or less puberulent, mostly 1-2 mm. wide; panicle dense, usually spikelike, often interrupted at base, pale-purple or often dark-purple, 5-15 cm. long, the axis and branches pubescent; spikelets 4-6 mm. long, the rachilla-joint shortly appressed-pilose, a iittle more than 1 mm. long, the callus-hairs very short; glumes somewhat unequal in length, glabrous or scabrous on the back, or sometimes pilose, the keels scabrous or ciliate, the first narrow, acuminate, 1 -nerved, the second broader, acute, 3-nerved; lemmas glabrous or scaberulous, 5 mm. long, the first longer than the glumes, the teeth setaceous; awn attached about one third below the tip, 5-6 mm. long, geniculate, exserted, flexuous at the base.
Type locality: Lapland.
Distribution: Alpine meadows and slopes, arctic America, southward to Connecticut, Pennsylvania, northern Michigan, and Minnesota; Roan Mountain. North Carolina; and in the mountains to New Mexico and California; the high mountains of Mexico and Central America; Hispaniola; also southward in the Andes to the antarctic regions and in the arctic and alpine regions of the Old World.

Annuals, Terrestrial, not aquatic, Stems nodes swollen or brittle, Stems erect or ascending, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly basal, below middle of stem, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath hairy, hispid or prickly, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades very narrow or filiform, less than 2 mm wide, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Leaf blades more or less hairy, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence a contracted panicle, narrowly paniculate, branches appressed or ascending, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence branches more than 10 to numerous, Flowers bisexual, Spikelets pedicellate, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 2 florets, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persis tent, Spikelets disarticulating below the glumes, Rachilla or pedicel hairy, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes equal to or longer than adjacent lemma, Glumes keeled or winged, Glumes 1 nerved, Glumes 3 nerved, Lemma similar in texture to glumes, Lemma 5-7 nerved, Lemma glabrous, Lemma apex dentate, 2-fid, Lemma distinctly awned, more than 2-3 mm, Lemma with 1 awn, Lemma awn less than 1 cm long, Lemma awn subapical or dorsal, Lemma awn once geniculate, bent once, Lemma margins thin, lying flat, Lemma straight, Callus or base of lemma evidently hairy, Callus hairs shorter than lemma, Palea present, well developed, Palea membranous, hyaline, Palea longer than lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.