Festuca of North America
Nord. J. Bot. 2: 530. 1982. Type: U.S.A. California: Inyo Co., Mono Mesa, 24 July 1946, J. T. Howell 22706. Holotype: CAS.
Habit. Plants bluish gray green, 4–10 cm high (culms less than twice the length of the basal leaves), densely tufted, tiller bases stiffly erect, bases not purplish, horizontal rooting stems absent. Vegetative shoots arising from within existing sheaths.
Vegetative morphology. Sheaths glabrescent (prophylls with trichomes on the veins, sometimes obvious at the base of the plant), not conspicuous at the base of the plant or conspicuous at the base of the plant, persisting for more than 1 year (not very conspicuous in small plants), remaining entire, not conspicuously splitting between the veins, closed more than half their length (Frederiksen 1982). Collars glabrous. Auricles represented by distinct, erect, swellings. Ligules 0.2–0.5 mm long, ciliate. Leaf blades 1.7–3.5 cm long, more or less lax. Adaxial blade surfaces with trichomes, abaxial blade surfaces glabrous. Leaf blades plicate; 0.25–0.39–0.55(–0.8) mm wide, 0.35–0.53–0.7 mm deep. Veins (3–)5. Adaxial to abaxial sclerenchyma strands absent. Abaxial sclerenchyma poorly developed, in discrete, relatively narrow strands opposite the veins. Ribs 1 (2–4 poorly developed lateral ribs). Uppermost culm leaf sheaths not inflated (or very slightly inflated). Flag leaf blades 0.8–2.5 cm long. Culm nodes never exposed; internodes glabrous.
Floral morphology. Inflorescence 0.8–2.5 cm long. Inflorescence branches at the lowest node 1–2, appressed after anthesis, 0.5–0.7 cm long. Rachis angular in cross section, trichomes mainly on the ridges. Spikelets aggregated towards the ends of the branches; 1–2 on the longest branches; (3.5–)4–5.2 mm long, 0.5–2 mm wide. Proliferating spikelets absent (not recorded for this taxon). Florets 2–4. Glumes unequal, glabrous, margins ciliate. First glume 2.4–3 mm long, veins 1. Second glume shorter than the first lemma, 3–4.3 mm long, veins 3. Lemma callus not elongated. Lemma 3.3–4.5 mm long, nerveless in dorsal view or sometimes with only the centre vein distinct, with trichomes, trichomes on the upper portion only; apex entire. Lemma awn 0.7–1.2 mm long. Palea 3–4 mm long, distinctly pubescent between the keels. Lodicules with marginal teeth, glabrous, 0.7–0.8 mm long. Anthers 0.9–1.4 mm long. Ovary apex glabrous. Caryopsis 1.8–2.2 mm long.
Cytology. 2n = 28 (Frederiksen 1982, based on guard cell measurements).
Habitat and Distribution. Native; alpine. Endemic in California on alpine sites in Sierra Nevada and White Mountains. Southwestern USA: Calif.
Classification. Subg. Festuca L.
These data where gathered, 1987–1990, from Californian specimens, following the recognition of this subspecies by Frederiksen (1982) and Aiken (1993). This taxon is now considered synonymous with F. brachyphylla subsp. coloradensis Frederiksen; see notes for that taxon (Aiken et al. 1997, illustrated in the image library).
• = F. brachyphylla subsp. coloradensis leaf anatomy. Leaf cross section of F. brachyphylla subsp. coloradensis based on the average of 10 samples from collections in California. Leaf blades are 0.35–0.65 mm wide and 0.35–0.95 mm deep, with 3–5(-7) veins. Adaxial to abaxial sclerenchyma strands are absent. Abaxial sclerenchyma strands are poorly developed, in discrete, relatively narrow strands opposite the veins, but sometimes more strongly developed than in arctic specimens of subsp. brachyphylla. There is one well defined rib and 2–4 variously defined lateral ribs. • Type specimen of name in synonymy: CAS. Type specimen of F. brachyphylla subsp. breviculmis, scanned from Frederiksen, S. (1982, with permission). U.S.A. California: Inyo Co, Mono Mesa, 24 July 1946, J. Th. Howell 22706. CAS.
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).