Festuca of North America
| Festuca of North America |
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Nomenclature
NORTHERN ROUGH FESCUE.
In Ledebour, Fl. Altaica 1: 109–110. 1829. F. altaica subsp. eu-altaica var. genuina subvar. typica St.-Yves. Candollea 2: 270. 1925. Type: Central Asia, Russia, Altai Mountains, "in summa alpe ad fontem fl. Acjulac rarissima", (translation: "Very rare on mountain summit at source of Acjulac River") C.B. Trinius s.n. Holotype and three possible isotypes LE (Tzvelev 1976).
F. scabrella Torrey in Hook., Fl. Bor. Am. 2: 252, tab. 233. 1840. F. altaica subsp. scabrella (Torrey) Hultén, Fl. Alaska and Yukon 1: 241. 1942. F. altaica var. scabrella (Torrey) Breitung, Am. Midl. Natl. 58: 12. 1957. Type: Canada. Alberta: Rocky Mountains, 1826, T. Drummond 187; Holotype: originally at NY, Torrey Herbarium; now at GH! "Ex. Herb. Torrey". Isotype: GH! Alexeev (1982) noted that the syntypes "Drummond" numbers "71, 187, 212" are at K and NY!
F. altaica forma pallida Jordal, Rhodora 54: 36. 1952. Type: U.S.A. Alaska: Brooks Range, near Wiseman, 19 June 1949, L. H. Jordal 1862. Holotype: MICH (Confirmed, Reznicek (MICH), personal communication 1995).
F. altaica forma vivipara Jordal, Rhodora 54: 36. 1952. Type: U.S.A. Alaska: Brooks Range, Wild Lake, 31 July 1949, L. H. Jordal 2471. Holotype: MICH. (Confirmed, Reznicek (MICH), personal communication 1995).
"F. altaica forma scabrella" (Torrey) Looman & Best, Budd's Flora Canad. Pr. Prov., Agric. Canada Research Branch Publ. 1662: 128. 1979, pro syn.
Habit. Plants yellowish green or deep green, (25–)30–90(–120) cm high, densely tufted, tiller bases stiffly erect, bases purplish (slightly reddish) or not purplish (usually), horizontal rooting stems present (as short stems between the tillers) or absent (not often observed on herbarium specimens). Vegetative shoots arising from within existing sheaths, or arising outside, or breaking through the base of existing sheaths.
Vegetative morphology. Sheaths glabrous or glabrescent, conspicuous at the base of the plant, persisting for more than 1 year, remaining entire, not conspicuously splitting between the veins, open more than half their length (prophylls 3–5 cm long with glabrescent, retrorse trichomes 0.4–0.7 mm long on the veins, occur among the sheaths). Collars glabrous. Auricles represented by distinct, erect, swellings or absent. Ligules 0.2–0.6 mm long, ciliate. Leaf blades (4–)10–30(–45) cm long, erect, stiffish. Adaxial blade surfaces with trichomes, abaxial blade surfaces with trichomes (illustrated Aiken and Lefkovitch 1984, p. 1868, in the image library). Leaf blades flat (occasionally) or plicate (usually), 2–4 mm wide (leaf widths in this taxon vary considerably which may be related to the presence of B chromosomes (Aiken and Fedak 1992). The larger leaves are often flat in the field, but roll during preservation. The illustration in Aiken et al. (1985) is that of a smaller leaf; the cross section illustrated in Aiken and Consaul (1995) is from a more average and relatively larger leaf); 0.5–0.79–1.4 mm wide, 0.65–0.96–1.2 mm deep. Veins 7–17. Adaxial to abaxial sclerenchyma strands present. Abaxial sclerenchyma poorly developed, in discrete, relatively narrow strands opposite the veins. Ribs 6–9 (well defined). Uppermost culm leaf sheaths not inflated. Flag leaf blades 2–8 cm long. Culm nodes never exposed; internodes glabrous, or scabrous-hirsute (minutely scaberulous, sometimes on the same plant, e.g. CAN 38206, collection from Alaska).
Floral morphology. Inflorescence 5–16 cm long. Inflorescence branches at the lowest node 1–3, spreading ("open to somewhat contracted, the lower branches spreading to ascending", Looman and Best 1979, p.128.), (3–)5–13 cm long (often secund, i.e. two branches arising from one side of the rachis and often blown in the same direction in a wind). Rachis rounded in cross section or angular in cross section, trichomes over the entire surface. Spikelets loosely scattered in an open panicle with slender branches (often purple); (2–)4–10 on the longest branches (spikelets borne towards the ends of the branches); 8–14 mm long, 2–5 mm wide. Proliferating spikelets absent. Florets 3–4(–6). Glumes unequal, glabrous or with trichomes (rarely scaberulous), vestiture at the apex only or over most of the outer surface (when applicable), margins ciliate (borders translucent). First glume (4–)4.2–6.8(–8.3) mm long, veins 1. Second glume shorter than the first lemma, (4.5–)5.3–7.5(–10) mm long, veins 1–3. Rachilla internodes antrorsely scabrous. Lemma callus not elongated. Lemma (6.5–)7.5–9(–12) mm long, with 5 distinct veins in dorsal view, with trichomes, trichomes over the entire surface; apex entire (illustrated by Pavlick and Looman 1984, p. 1741 and in the image library). Lemma awn 0.2–0.7 mm long. Palea 6–9(–11) mm long (almost as long as the lemma), distinctly pubescent between the keels. Lodicules with marginal teeth, ciliate, 1–1.5 mm long. Anthers 2.6–4.5(–5) mm long. Ovary apex pubescent. Caryopsis 4–5 mm long.
Cytology. 2n = 28 (+ B chromosomes, Aiken and Fedak, 1992. W.W. Mitchell, University of Alaska, Agricultural Experimental Station, Palmer, Alaska made an unpublished count of 2n=56, personal communication 1990. A specimen collected in Michigan, Otsego Co., Dore 21169 had 2n=28 T. Mosquin, March 1965. DAO. Two specimens from Quebec, Ungave, Lepage 39,502, 39,524 had 2n=28. T Mosquin, March 1965, DAO.).
Habitat and Distribution. Native; arctic, or alpine. And Asia; Canada: Labrador, Nfld., Que., B.C., Mackenzie District (NWT), Yukon; Northwestern USA: Alaska; Northeastern USA: Mich.
Classification. Subg. Leucopoa (Griseb.) Hack. (subg. Hesperochloa, sect. Breviaristatae Krivot, Alexeev (1980)).
Notes
There has been constant agreement that this is a distinct species (Pavlick and Looman 1984, Alexeev 1985, Harms 1985, Aiken and Darbyshire 1990, Gleason and Cronquist 1991). Characters useful for distinguishing this species from other rough fescues are in the notes for F. campestris Rydb.
Illustrations
• Habitat and inflorescence. Habitat and inflorescence of F. altaica. Left, a zone dominated by F. altaica in the China Head Mountains of British Columbia. Right, inflorescences photographed against the skyline to show the drooping angles of the branches. • Habitat in Northern Yukon. The reddish zone towards the foreground of this picture is dominated by bunches of F. altaica (a bunch is indicated by the arrow). Caribou in the distance had been grazing in this area, which was an unusually grassy area of the "barren" lands. • Leaf anatomy. Leaf cross section of F. altaica. Plicate leaf blades are 0.5–0.79–1.4 mm wide and 0.65–0.96–1.2 mm deep, with 7–17 veins. Adaxial to abaxial sclerenchyma strands are present. Abaxial sclerenchyma strands are poorly developed, in discrete, relatively narrow strands opposite the veins. There are 6–9 well defined ribs. • Holotype of controversial specimen: NY. Holotype of the Drummond collection of F. altaica that became the type specimen of F. scabrella. The main label reads. "Type? F. scabrella n. sp! Hook. Fl. Bor. p.253. 6.233. Sheaths scabrous... with minute hairs, Rocky Mountains. T. Drummond. Hooker". The faded label reads "this is the typical plant distinguished by the small size and smaller spikelets, and no ligule. It occurs well north of the Rocky Mountains. It extends to the Gaspe region in Canada F. (Fernald)". This specimen has been annotated as a lectotype by L.E. Pavlick and as an isosyntype by A. Alexeev. • Controversial Drummond isotype specimens: GH. Drummond collections of F. altaica housed at the Gray Herbarium. Left, the original sheet appears to have been cut around the plant material on the left hand side of the sheet and mounted onto a second sheet with no more information on the entire sheet than is shown on the right hand side. On the extreme left the words along the border read, " F. Thurberi V = scabrella". The writing at the bottom left hand corner is, "Rky. Mt. Drummond". The specimen was photographed by Agriculture Canada as number 279. The upper annotation reads, "Festuca altaica Trin. in Ledeb. (possible isotype of F. scabrella Torr. in Hook.) Determined by Leon E. Pavlick, B.C. Provincial Museum, Victoria. Sept. 1981." The lower annotation reads, "probably isotype of Festuca scabrella Torr. in Hook. (nix Thurberi!) Aug. 27 1947. C.A. Taylor Jr."(C.A. Taylor was a student of H.A. Gleason at Cornell University who began a thesis study of Festuca but never finished it). Right, a second sheet that appears to be the other half of the sheet on the left. This has been stamped ISOTYPE. The annotation beside the stamp reads, "Festuca scabrella Torr. in Hook. Fl. Bot. Am. 2. p. 252. t. 233. Rocky Mts. Hook. ex. Torr. Drummond (original stook)". A second closely associated label reads, "Ex. Herb. George Thurber (Purchased 1800)". • Genotypic variation. Fig. 1. Festuca altaica collection from the Yukon with relatively long and wide, flat leaves. W.J. Cody 27968. Plants like this, S.G. Aiken 90–078, had 2n=28 chromosomes. Fig. 2. F. altaica collection of plants from the same Yukon site as those in Fig. 1, W.J. Cody 27696. The leaves are conspicuously shorter and inrolled so that they appear very narrow. Plants like this, S.G. Aiken 90–079, had 2n=28 + 2B chromosomes. Fig. 3. Somatic metaphase plate of F. altaica collection S.G. Aiken 90–079, showing a chromosome number of 2n=28 + 2B. Arrows point to the two B chromosomes. 4800 x. Fig. 4. Somatic metaphase plate of F. altaica, S.G. Aiken, 90–079 showing a chromosome number of 2n=28 + 2B. Arrows point to the two B chromosomes. Present also are fragments deleted from other chromosomes. 3000 x. (Original pictures in Aiken and Fedak, 1992). • 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).
