Flora of the Canadian Arctic Archipelago
Poaceae, Grass family.
Published in Nom. cons., Prodr. 1: 208. 1810.
Vegetative morphology. Plants 5–40 cm high; perennial herbs; caespitose, or not caespitose. Only fibrous roots present. Ground level or underground stems horizontal; rhizomatous; elongate, or compact; 0.3–2 mm wide. Ground level or underground stems scales present; surfaces smooth, or striate; 10–20 mm long; glabrous. Aerial stems erect. Leaves mainly basal, or distributed along the stems; alternate; marcescent. Petioles absent. Sheaths present; persisting; with the margins fused only in the lower part; glabrous, or with trichomes; scabrous; sheath collars present. Ligules present; 0.2–1.3 mm long; membranous, or a fringed membrane; glabrous, or hairy; ovate-oblong. Ligule apices obtuse, or truncate; entire, or erose, or lacerate. Leaves grass-like. Blades 10–120 mm long, 0.7–3.4 mm wide, appressed to the stem or spreading, rolled in bud, linear, flat or involute, veins parallel, midvein conspicuously larger than the lateral veins or midvein similar in size to other veins in the leaf. Blade adaxial surface hairy. Blade abaxial surface glabrous.
Reproductive morphology. Flowering stems circular or oval in cross section. Flowering stems with leaves; culm nodes not exposed. Flag leaf sheaths inflated, or not inflated. Inflorescences paniculate; dense, or diffuse; linear, or ovate; 1–3 cm long; 3–20 mm wide. Inflorescences main axis glabrous. Number of inflorescence branches at lowest node 1, or 2. Inflorescence primary branches 0.5–12 mm long; glabrous; with appressed secondary branches, or with spreading secondary branches. Spikelets disarticulating above the glumes; ovate, or obovate; 3.5–7.2 mm long; 2–6 mm wide. Florets per spikelet 3. Two glumes present. First glume 0.8–1 × the length of the second glume; 0.75–0.95 × spikelet length; 2.9–6.7 mm long; lanceolate, or ovate; glabrous; margins glabrous; veins 1–3; apex acute. Second glume as long or longer than the spikelet; almost as long as, or longer than, the lowest floret; 3.5–7 mm long. Second glume lanceolate, or ovate. Second glume glabrous; veins 1–3. Rachilla internode 0.9–1.1 mm long; glabrous. Callus differentiated, or not differentiated; hairs shorter than the floret. Lemma ovate, or lanceolate; 2.9–4.4 mm long; keeled, or rounded on the back; surface dull; surface hairy; veins 3–6; apex acute; apex entire; apex ciliate; awned, or awnless. Awn arising from below the apex but above the middle. Awn 0.5–1.5 mm long (if applicable). Palea well developed; 2.4–4.4 mm long; veins hairy. Flowers bilaterally symmetrical (zygomorphic). Perianth represented by lodicules. Stamens 3. Anthers 1.5–3 mm long. Ovary superior; carpels 3; syncarpous. Ovaries glabrous. Styles 2. Placentation basal. Ovules per ovary 1. Fruit sessile; dry; a caryopsis; 2.5–3 mm long; indehiscent. Seeds 1.
North American distribution. Range in the Canadian Arctic Archipelago widespread.
General notes. Veldkamp, in Schouten and Veldkamp (1985), merged Hierochloe and Anthoxanthum under the latter (priority) name and recombined several species of Hierochloe as Anthoxanthum. The two genera are quite different morphologically in Europe and North America, but Asian representatives are much more similar (Elven observation, 2005). As this CD was going to press, Hierochloe was included in Anthoxanthum by Allred and Barkworth (2007) in Flora of North America.
This publication is available on the internet (posted May 2011) and on CD-ROM (published in 2007). These versions are identical in content, except that the errata page for CD-ROM is accessible on the main index page of the web version.
Recommended citation for the web-based version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. NRC Research Press, National Research Council of Canada, Ottawa. http://nature.ca/aaflora/data, accessed on DATE.
Recommended citation for the CD-ROM version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. [CD-ROM] NRC Research Press, National Research Council of Canada, Ottawa..