Anthoxanthum nitens

(Weber) Y. Schouten & Veldkamp
Common names: Vanilla sweetgrass Hierochloe odorante Foin d'odeur Herbe sainte
Synonyms: Hierochloe odorata Hierochloe borealis
Treatment appears in FNA Volume 24. Treatment on page 762.

Plants perennial; loosely cespitose or the culms solitary, rhizomes elongate, 0.7-2 mm thick. Culms (5) 15-50 (90) cm. Sheaths brownish or reddish, glabrous or puberulent; ligules 0.5-6.5 (8) mm, truncate, obtuse, or acute; blades 10-30 cm long, 2-8 mm wide, usually flat, sometimes inrolled, abaxial surfaces glabrous or pubescent, without prominent cross venation, adaxial surfaces glabrous; flag leaf-blades 0.3-1.5 (4.5) cm long, 1.5-4.5 (6) mm wide. Panicles (2) 4-9 (12.5) cm long, (1.5) 2-5 (7) cm wide, open, pyramidal, with 8-100 spikelets; branches with 3+ spikelets. Spikelets (2.5) 3.5-7.5 mm, mostly tawny, sometimes tinged with green; rachilla internodes 0.15-0.3 mm, glabrous. Glumes subequal, exceeding the florets, glabrous; lower glumes with lengths 2-5 times widths, usually shorter and wider than the upper glumes; lowest 2 florets staminate; lemmas hairy, particularly distally, hairs brown, often papillose-based, to 0.8 mm on the margins and to 0.3 mm near the apices, margins with 11-26 hairs per mm, midvein usually terminating at the apices or extending beyond as an awn, apices acute to rounded, entire or bifid, unawned, mucronate, or with a thin awn, awns to 0.5 mm; first lemma 3.4-5 mm long, 1-1.5 mm wide, length usually less than 4 times width, elliptic; bisexual lemmas 2.5-4 mm, usually hairy distally, hairs 0.1-0.5 mm, appressed or almost so at maturity, longer, divergent hairs, if present, concentrated near the midvein; anthers of staminate florets 0.9-2.3 mm, those of bisexual florets 1.2-1.6 mm. 2n = 28, 42.

Discussion

Anthoxanthum nitens is primarily a European species. In the Flora region, it grows along the coast from northern Labrador to New England. It is not known from Greenland, although it grows in Iceland and northwestern Europe. It grows in wet meadows and at the edges of sloughs, marshes, roadsides, and fields. Only A. nitens (Weber) Y. Schouten & Veldkamp subsp. nitens is present in the region; it is also present in Europe. It differs from A. nitens subsp. balticum (G. Weim.) G.C. Tucker in being almost always awned and having In = 28.

North American taxonomists have generally interpreted Anthoxanthum nitens as including A. hirtum (and treated both as Hierochloe odorata (L.) Wahlenb.). The two are distinct, although not easy to distinguish. Weimarck (1971) separated the two by the density of the lateral hairs and development of the awns of the staminate florets. The difference in abundance and distribution of hairs more than 0.5 mm long on the apices of the bisexual florets is more reliable, A. nitens having few such long hairs concentrated near the midvein. M.J. Harvey (pers. comm.), who did not distinguish between the two species, found that plants from the Maritime Provinces collected near saltwater were uniformly 2n = 28, whereas those from the interior of New Brunswick westward had 2n = 56. This observation is consistent with Weimark's chromosome counts and distribution maps.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Anthoxanthum nitens"
pubescent +  and glabrous +
membranous +  and scarious +
3 +  and 2 +
awned +  and bilobed +
Kelly W. Allied +  and Mary E. Barkworth +
(Weber) Y. Schouten & Veldkamp +
1 (?) +  and 3 (?) +
straight +
basal +  and terminal +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
not evident +
pilose +  and glabrous +
rolled +  and flat +
0.2 cm2 mm <br />0.002 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
spikelike +
hairy +  and glabrous +
Vanilla sweetgrass +, Hierochloe odorante +, Foin d'odeur +  and Herbe sainte +
geniculate +
15 cm150 mm <br />0.15 m <br /> (50 cm500 mm <br />0.5 m <br />) +
not woody +
Conn. +, N.J. +, N.Y. +, Wash. +, Del. +, D.C +, Wis. +, W.Va. +, Alta. +, B.C. +, Greenland +, Man. +, N.B. +, Nfld. and Labr. +, N.S. +, N.W.T. +, Nunavut +, Ont. +, P.E.I. +, Que. +, Yukon +, Pacific Islands (Hawaii) +, Mass. +, Maine +, N.H. +, R.I. +, Vt. +, Fla. +, N.Mex. +, Tex. +, La. +, Tenn. +, N.C. +, S.C. +, Pa. +, Alaska +, Va. +, Colo. +, Iowa +, Miss. +, Calif. +, Ala. +, Ark. +, Ill. +, Ga. +, Ind. +, Okla. +, Idaho +, Md. +, Ohio +, Mo. +, Minn. +, Mich. +, Oreg. +, Mont. +  and Ky. +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
sometimes longer +
compressed +
reduced +
shorter or longer +
subtending +
keeled +, lanceolate +  and ovate +
subequal +
exceeding the florets +  and equaling +
papillose-based +
almost +  and appressed +
11 +  and 26 +
uncinate +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
0 +  and 1/3 +
hairy +  and glabrous +
3-7-veined +  and 3-veined +
0.34 cm3.4 mm <br />0.0034 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
compressed +
subequal +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
1mm +  and 1.5mm +
acute +, obtuse +  and truncate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
membranous +
inconspicuous +
lanceolate +
usually shorter and wider +
mucronate +, acute +  and rounded +
concealed +  and prominent +
2 +  and 1 +
hairy +  and glabrous +
well-developed +
2-keeled +
4cm +  and 9cm +
pyramidal +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
dry +  and fleshy +
not prolonged +
puberulent +  and glabrous +
sessile +  and pedicellate +
tinged with green +  and tawny +
8 +  and 100 +
compressed +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Hierochloe odorata +  and Hierochloe borealis +
Anthoxanthum nitens +
Anthoxanthum +
species +
membranous +
parallel +  and converging +
plant +  and cespitose +
aquatic +  and terrestrial +