Festuca of North America

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S. G. Aiken, M. J. Dallwitz, C. L. McJannet, and L. L. Consaul

Festuca dasyclada Hack. ex Beal

Nomenclature

Grasses N. Am. 2: 602. 1896. Argillochloa dasyclada (Hack. ex Beal) W.A. Weber, Phytologia 55: 1. 1984. Type: U.S.A. central Utah: Rocky Mountains, 1875, C. C. Parry 93. The type specimen was in the herbarium of Prof. Scribner that was destroyed by fire. A duplicate at US! has no locality on the label. Isotype: GH! The GH isotype specimen has more material at the base of the plant than the holotype, but no strong evidence of rhizomes.

Habit. Plants bluish gray green, 20–40 cm high, densely tufted, tiller bases not stiffly erect, bases purplish, horizontal rooting stems present (short). Vegetative shoots arising outside, or breaking through the base of existing sheaths.

Vegetative morphology. Sheaths glabrous, not conspicuous at the base of the plant, splitting between the veins, open more than half their length. Collars glabrous. Auricles represented by distinct, erect, swellings or absent. Auricular cilia present, long and pilose-like. Ligules 0.2–0.5 mm long, ciliate (cilia prominent). Leaf blades 5–15(–20) cm long, more or less lax. Adaxial blade surfaces with trichomes, abaxial blade surfaces glabrous. Leaf blades flat or plicate (loosely rolled), 0.6–2 mm wide; 0.5–0.82–1 mm wide, 0.6–0.82–1 mm deep (cross sections are usually as wide as long). Veins 7–10. Adaxial to abaxial sclerenchyma strands absent. Abaxial sclerenchyma well developed, in discrete, relatively narrow strands opposite the veins. Ribs 6–9. Uppermost culm leaf sheaths somewhat inflated, or not inflated. Flag leaf blades 2–6 cm long. Culm nodes becoming exposed (sometimes dark purple), 2; internodes densely pubescent (similar to those of F. baffinensis).

Floral morphology. Inflorescence 6–12 cm long. Inflorescence branches at the lowest node 1–4, spreading (almost at right angles to each other), 4–6 cm long (lower branches conspicuously pulvinate). Rachis angular in cross section, trichomes mainly on the ridges (prominent and conspicuously ciliate). Spikelets loosely scattered in an open panicle with slender branches; 3–5 on the longest branches; 5.5–8 mm long, 3–5 mm wide. Proliferating spikelets absent. Florets 2 (usually). Glumes unequal, with trichomes, vestiture at the apex only (and along the keel), margins ciliate (slightly). First glume 3.5–4.5(–5) mm long, veins 1. Second glume as long as the first lemma, or almost as long, 5–7 mm long, veins 3. Rachilla internodes 1–1.5 mm long, antrorsely scabrous. Lemma callus not elongated. Lemma 5–7 mm long, nerveless in dorsal view or sometimes with only the centre vein distinct, with trichomes (sparse), trichomes on the upper portion only; apex entire. Lemma awn 2–3 mm long. Palea 4.5–6.5 mm long, distinctly pubescent between the keels. Lodicules with marginal teeth, glabrous, 0.7–0.8 mm long. Anthers 1.5–2.5 mm long. Ovary apex pubescent. Caryopsis 3.5–4.5 mm long.

Cytology. 2n = 28.

Habitat and Distribution. Native; alpine, or rangeland, prairie, dry habitats. Rocky Mountains USA: Colo., Utah ("rocky slopes; endemic to central Utah. A very distinct species that has been recollected only once in the Wasatch Plateau", Cronquist (1977). Welsh et al. (1987) reported the species as growing chiefly in sagebrush, mountain brush and juniper communities at 2130–3048 m in the Utah Counties Emery (the type specimen is from Joes Valley), Garfield, Sanpete and Wasatch and also western Colorado. We have examined 10 collections from Colorado and 3 from Utah).

Classification. Subg. Festuca L.

Notes

This species was placed in a monotypic genus by Weber (1984) as Argillochloa dasyclada, but this has been refuted by Aiken et al. (1992) and Darbyshire and Warwick (1992). No reason for separating this species from Festuca is apparent in the analyses by Lefkovitch (1993). In phenotypic and cladistic analyses, using this database, the position of F. dasyclada varied considerably in different analyses. Seed protein evidence, anatomy, and a general lack of characters beyond the inflorescence structure discourage recognizing this taxon as a distinct genus.

The following are details from notes on the isotype specimen at GH (illustrated in the image library). The label at the bottom left hand corner reads, "Flora of central Utah. No. 93. Coll. C.C. Parry. 1895". The letter on the upper right hand side reads as follows, with (?) indicating hand written words that could not be interpreted. "Dupl. Muhlenbergia? Dr. Thurber. Culms erect from a perennial (?) root, about 1-foot high, scabrous below the panicle and pubescent below the nodes, otherwise smooth; leaves (?) long about a line wide, strongly pubescent on the upper surface, nearly smooth below, rough on the margins, the uppermost reduced to a mere sheath; ligule a hairy fringe; sheaths loose, smooth, or minutely pubescent between the striae; panicle about 4 inches long, open, few flowered; rays in pairs, subdivided in a similar manner above the middle, much flattened and 2-edged or, with the apis 3-angled, strongly ciliolate fringed on the angles, pale yellowish green throughout; spikelets exclusive of awn, 2 lines long with pedicels mostly much longer; glumes herbaceous, hyaline on the margins, lanceolate, acute or somewhat acuminate, ciliate on the keel towards the apex, the upper one third the longer and barely equalling the floret, its lateral nerves evanescent towards the apex; floret lanceolate with a distinct rounded smooth callus accompanied by a conspicuous rudiment of a second flower; lower palet of firmer texture". C.A. Taylor Jr. has written, "Isotype: part of sole known collection. August 27, 1947". Under the hand written label, "Festuca dasyclada Hack." is printed, "Named by F. Lamson-Scribner".

Illustrations

• Habitat and close up. Left, plants growing on steep slope (white arrows) in Utah, Wasatch Co., Buffalo Canyon, Uinta National Forest where sheep were grazing. Right, close up of plant showing divaricating branches of the inflorescence. • Line drawing. Illustration from Scribner (1901). The description with the illustration describes spikelets as usually 2-flowered, about 7 mm long, glumes unequal, the second glume with 3 veins, and the lemmas (flowering glumes) about 6 mm long, scabrous and with 5 veins. • Leaf anatomy. Leaf cross section of F. dasyclada. Leaf blades are 0.5–0.82–1 mm wide and 0.6–0.82–1 mm deep, cross sections are usually as wide as long, with 7–10 veins. Adaxial to abaxial sclerenchyma strands are absent. Abaxial sclerenchyma strands are well developed, in discrete, relatively narrow strands opposite the veins. There are 6–9 ribs. • Habitat in Utah Uinta National Forest. Habitat of F. dasyclada, which are the larger browner grasses (white box, lower left). Festuca saximontana was growing at the same site as smaller more tufted plants, closely associated with the sage plants. • Holotype specimen: NY. Holotype specimen of F. dasyclada. Label reads," Ex. Herb. J.H. Redfield. No. 93 Festuca Central Utah S.C.(?) C.C. Parry. 1875". Although this is the holotype, it has less plant material than does the isotype housed at GH. U.S.A. central Utah: Rocky Mountains, 1875, C.C. Parry 93. NY. • Isotype specimen: GH. Type specimen of F. dasyclada. Label at the bottom left hand corner reads, "Flora of central Utah. No. 93 Coll. C.C. Parry. 1875". Letter on upper right hand side reads, "Dupl Muhlenbergia? Dr. Thurber Culms erect from a perennial (?) root, about 1-foot high, scabrous below the panicle and pubescent below the nodes, otherwise smooth; leaves (?) long about a line wide, strongly pubescent on the upper surface, nearly smooth below, rough on the margins, the uppermost reduced to a mere sheath; ligule a hairy fringe; sheaths loose, smooth, or minutely pubescent between the striae; panicle about 4 inches long, open, few flowered; rays in pairs, subdivided in a similar manner above the middle, much flattened and 2-edged or, with the apis 3-angled, strongly ciliolate fringed on the angles, pale yellowish green throughout; spikelets exclusive of awn, 2 lines long with pedicels mostly much longer; glumes herbaceous, hyaline on the margins, lanceolate, acute or somewhat acuminate, ciliate on the keel towards the apex, the upper one third the longer (glume) and barely equaling the floret, its lateral nerves evanescent towards the apex; floret lanceolate with a distinct rounded smooth callus accompanied by a conspicuous rudiment of a second flower; lower palet of firmer texture". C.A. Taylor Jr. has written, "Isotype: part of sole known collection. August 27, 1947". Under the hand written label "F. dasyclada Hack." is printed, "Named by F. Lamson-Scribner". • Distribution map


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).

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