Festuca of North America
Can. J. Bot. 62: 2457. 1984. Type: Canada. British Columbia: Liard River Basin, Fairy Lake, 26 July 1977, Argus and Haber 9987. Holotype: V. Isotype: CAN!
Habit. Plants bluish gray green, 13–25 cm high, not densely tufted (usually), tiller bases stiffly erect or not stiffly erect, bases purplish or not purplish, horizontal rooting stems present or absent. Vegetative shoots arising outside, or breaking through the base of existing sheaths.
Vegetative morphology. Sheaths glabrous or glabrescent or with trichomes (sometimes with retrorse hairs similar to F. rubra, e.g. on isotype), not conspicuous at the base of the plant, splitting between the veins (brownish), closed more than half their length (Pavlick 1984) or open more than half their length (Aiken unpublished). Collars glabrous. Auricles represented by distinct, erect, swellings. Auricular cilia absent. Ligules 0.1–0.2 mm long, ciliate. Leaf blades 5–16 cm long, more or less lax. Adaxial blade surfaces with trichomes, abaxial blade surfaces with trichomes (uniformly scabridulous). Leaf blades plicate; 0.4–0.5–0.6 mm wide, 0.6–0.7–0.85 mm deep. Veins 5–7. Adaxial to abaxial sclerenchyma strands absent. Abaxial sclerenchyma poorly developed (sclerenchyma strands 5–7, narrow, the width less than 2 times the height.). Ribs 1 (well defined, 2–4 variously defined). Uppermost culm leaf sheaths not inflated. Flag leaf blades 1.4–3.5 cm long. Culm nodes becoming exposed, 1 (if visible); internodes glabrous (usually, a Yukon collection, CAN 270342, has sparsely hairy culms).
Floral morphology. Inflorescence branches at the lowest node 1, appressed after anthesis, 0.3–1 cm long. Rachis angular in cross section, trichomes mainly on the ridges or trichomes over the entire surface. Spikelets 1–2 on the longest branches; 7–25 mm long (including vegetative proliferation), 1.5–3 mm wide. Proliferating spikelets present. Florets 1–4 (any floret from the lowest to the fourth or higher may proliferate). Glumes unequal, with trichomes, vestiture over most of the outer surface (scabrous), margins not ciliate. First glume 3–4.2 mm long, veins 1. Second glume shorter than the first lemma (usually), 4.2–5.3 mm long, veins 3. Lemma callus not elongated. Lemma 4.8–6.9 mm long, nerveless in dorsal view or sometimes with only the centre vein distinct, with trichomes (to 0.3 mm long), trichomes on the upper portion only; apex entire. Lemma awn 0–0.8 mm long. Palea 4.8–5.2 mm long (usually absent), distinctly pubescent between the keels. Anthers 2 mm long (approximately, if present). Ovary apex glabrous.
Cytology. 2n = unknown.
Habitat and Distribution. Alpine. Canada: Alta., B.C., Yukon.
Classification. Subg. Festuca L.
Morphological data in the data base were collected from specimens that had grown in the western Cordillera and formed the basis of the description in Aiken and Darbyshire (1990).
Pavlick (1984) recognized two entities within F. viviparoidea. The typical subspecies, subsp. viviparoidea, is circumpolar with Canadian collections only from Ellesmere Island. The form found in alpine sites in the western cordillera is referred to as subsp. krajinae Pavlick. This treatment was not followed by Alexeev (1985) who presented four rather different leaf cross sections under the name F. viviparoidea.
The interactive key provides access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, and summaries of attributes within groups of taxa.
Cite this publication as: ‘Aiken, S.G., Dallwitz, M.J., McJannet, C.L. and Consaul, L.L. 1996 onwards. Festuca of North America: descriptions, illustrations, identification, and information retrieval. Version: 19th October 2005. http://delta-intkey.com’. Aiken, Dallwitz, McJannet, and Consaul (1997) should also be cited (see References).