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Notes on the taxonomy and nomenclature of Festuca occidentalis and F . idahoensis LEONE. PAVLICK Botany Division, British Columbia Provincial Museum, Victoria, B.C., Canada V8V 1x4 Received August 10, 1981

L. E. 1983. Notes on the taxonomy and nomenclature of Festuca occidentalis and F. idahoensis. Can. J . Bot. 61: PAVLICK 337-344. Festuca occidentalis occurs in open forests and glades, always in at least partial shade. In British Columbia it occurs from the U.S.A. border to about latitude 57" N. It has leaf structure, panicle structure, spikelet length, glume length, lemma length, lemma scabrosity, awn length, anther length, and ovary vestiture which are different from F. idahoensis. Festuca idahoensis is found in grasslands (including subalpine meadows) and in openings in dry forests bordering grasslands, always in open, nonshaded situations. In British Columbia it occurs from the U.S.A. border northward to about 51" N. Despite the recent lumping of these two taxa, morphological and ecological evidence strongly suggests that they should be treated as separate species.

PAVLICK L. E. 1983. Notes on the taxonomy and nomenclature of Festuca occidentalis and F. idahoensis. Can. J . Bot. 61: 337-344.

Festuca occidentalis croit dans les forets ouvertes et les clairitres, toujours dans des endroits au moins partiellement ombragts. En Colombie-Britannique, il se rencontre de la frontitre amtricaine jusqu'h environ le 57" N. I1 difftre de F. idahoensis par la

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structure des feuilles et de la panicule, par la longueur des tpillets, des glumes et des lemmas, par la scabrtitt du lemma, la longueur de l'arete, la longueur de I'anthtre et la pubescence de I'ovaire. Festuca idahoensis se rencontre dans les prairies (y compris les prairies subalpines) et dans les ouvertures des for& stches c6toyant les prairies, toujours dans des endroits ouverts et non ombragts; en Colombie-Britannique, il se rencontre de la frontitre amtricaine jusqu'au 51" N environ. Meme si ces deux taxons ont rtcemment ttC fondus en un seul, les donntes morphologiques et tcologiques montrent qu'il est prtftrable de les considtrer cornrne deux esptces distinctes. [Traduit par le journal]

spikelets, lemmas, awns, and anthers. Festuca ovina Introduction Hooker (1840) first described Festuca occidentalis has a chromosome number of 2n = 14 (Frederiksen from "plains and elevated grounds of the Columbia near 1981), while F. idahoensis has 2n = 28 (Hitchcock et the sea" and since then most botanists (e.g., Macoun al. 1969). From my own observations F . idahoensis is 1888; Beal 1896; St.-Yves 1925; Hitchcock 1951; also different from other taxa of the F . ovina complex in Hitchcock et al. 1969; Taylor and MacBryde 1977; North America (e.g .,F . saximontana Rydb., F. brachyLooman and Best 1979) have regarded it as distinct from phylla Schult. & Schult., F . bafinensis Polunin) in F. ovina L. having distinctly longer panicles, spikelets, lemmas, The taxon we now recognize as F . idahoensis was awns, and anthers. Because of the above dissimilarities I initially included in F . ovina L. under three different think F . idahoensis to be not only a distinct species from names: var. ingrata Hack. ex Beal; var. oregona Hack. F. ovina L. sensu stricto but also taxonomically well ex Beal; and var. columbiana Beal. Elmer (1903) separated from other members of the F. ovina complex described F . idahoensis without connecting it to the F . in North America. ovina varieties listed above. The name F. idahoensis Boivin (1967) included F . idahoensis in F . occidenwas not immediately taken up. Piper (1906) in his talis Hook. as F . occidentalis Hook. var. ingrata monograph on North American Festuca treated F . (Hack. ex Beal) Boivin. Reasons were not given for this idahoensis as F . ovina ingrata Hack. ex Beal and listed change. Boivin (1979) published the new combination as synonyms F . idahoensis and F . ovina varieties F. occidentalis Hook. var. oregona (Hack. ex Beal) columbiana and oregona. Eventually F. idahoensis was Boivin, transferring var. oregona (one of the taxonomic generally recognized as a species distinct from F. ovina elements generally included in F . idahoensis) from F. (e.g., Abrams 1923; St.-Yves 1925; Peck 1941; Hitch- ovina L. Reasons were not given for this change. cock 1951; Moss 1959; Hitchcock et al. 1969; Taylor Scoggan (1978) has followed Boivin, using the name F. and MacBryde 1977;Cronquist et al. 1977; Looman and occidentalis var. ingrata for the F . idahoensis taxon in Best 1979). Pavlick (1982) pointed out that F. idahoen- western Canada. sis has a very different leaf sclerenchyma pattern from During preliminary fieldwork and examination of the European F . ovina L. and distinctly longer panicles, herbarium specimens I carried out as part of a larger 0008-4026/83 /010337-08$01 .OO/O 01983 National Research Council of Canada/Conseil national de recherches du Canada


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TABLE1. Comparison of Festuca occidentalis with F. idnhoensis var. idnhoensis and var. roemeri. Values in parentheses are extreme values recorded from individual specimens

F. occidentalis Leaf shape Leaf sclerenchyma pattern Leaf flexibility Leaf surface tone (abaxial) Leaf vestiture (abaxial) Panicle structure Panicle length, cm Panicle branch flexibility Spikelet length, mm Lower glume length, mm Upper glume length, mm Lowermost lemma length, mm Lemma vestiture Lemma awn flexibility Lemma awn maximum length, mm Anther length, mm Ovary crown vestiture Habitat

F. idahoensis var. idahoensis

Irregular hexagon with elongate keel, sharp angled As in Fig. 1 Soft Green, glossy

F. idahoensis var. roemeri

Hexagonal, short keel, rounded angles As in Fig. 2 Stiff Green and moderately shiny, or glaucous Scaberulous Scabrous Mostly nodding, mostly open Mostly erect, mostly narrow 9.0-13.0 7.0-1 1.0 Flexible Stiff 6.5-9.0 8.0-13.5 2.4-3.6 2.4-4.3 3.2-4.4 4.0-5.7

See Pavlick (1982) Stiff Green and moderately shiny, or glaucous Glabrous to scabrous Mostly erect, mostly narrow 8.0-16.0 Stiff 9.0-13.5 2.5-5.0 4.0-6.2

Very scabrous on upper half Weak, often flexuous

Scabrous near tip Rigid, not flexuous

Scabrous near tip Rigid, not flexuous

4.0-8.0, often exceeding lemma in length 1.4-1.9 Densely hispid Forest

3.0-6.0(7.0), shorter than lemma in length 2.4-3.8 Glabrous Open areas

(2.5)3.0-5.0, shorter than lemma in length (2.6)2.8-3.6 Glabrous Open areas

study of Festuca in western Canada, I noted that whereas F , idahoensis was a plant of open areas, F . occidentalis was always associated with forests. F ~ tuca occidentalis was also found to have a more extensive range in western Canada than previously (Scoggan gave a broad Outline Of range) and this was much more extensive than that Of F . idahoensis. I decided to inquire into the problem of the relationship between F . occidentalis and F . idahoensis based on material from western Canada.

Materials and methods I have examined about 170 specimens of F. occidentalis and 150 of F , idahoensis from several herbaria (ACK, CAN, DAO, LEA, UAC, UBC, V, WTU)~.~h~~~ were all examined under a maximum sox dissecting microscope^ ~ 1 specimens in the study were identified and annotated and their distribution (Fig. 11) and habitat, as reported on the labels, recorded. Representative specimens from widely separated 'Acronyms from P. K. Holmgren, W. Keuken, and E. Schofield (compilers). 1981. Index Herbariorum. Bohn, Scheltema & Holkema, Utrecht.

Obovate-pyriform

areas were scored for at least 18 characters (Table 1). Values in Table 1 and in the key below are based on this scoring. Also I ~viewed - in-the-field and collected specimens of F. occidentalis (Vancouver Island, Cariboo District, Tahltan Highland) and F. idahoensis (Vancouver Island, South Thompson River Valley, Okanagan-Similkameen River valleys, east Kootenay River Valley). Specimens collected are on file at V, I also examined the types of the following taxa: holotype, F. ovina var. ingrata Hack. ex Beal, ~ ~ ~ ~ 1Oregon 1 2 3(US); , holotype, F . ovina var. oregona Hack. ex Beal, Cusick 753, Oregon (US); holotype, F. idahoensis Elmer. Abrams 688, Smith's Meadow, Shoshone Co., Idaho (DS); Syntype, F. occidentalis Hook., Douglas s.n., plains of the Columbia (GH). (In my recent correspondence (28 April 1981) from the Royal Botanic Gardens, Kew, Dr. Thomas A. Cope indicated that Dr. E. Alexeev of Moscow had recently selected a 1 lectotype of F. occidentalis from one of three specimens at K which seem to be qualified. Its labels indicate Douglas "on the plain of the Columbia near the sea'' and "224 Same as 147.") The Douglas specimens in GH were considered "authentic specimens from Hooker" by Piper (1906). Charles A. Taylor has annotated one specimen in GH as an isotype of F. occidentalis. Hooker (1840) based his description of F. occidentalis on specimens collected by Dr. Scouler and by Douglas. There was no holotype and therefore there were no

FIGS.1 and 2. Leaf cross sections. Fig. 1. Festuca occidentalis. x 180. Fig. 2. Festuca idahoensis var. idahoensis. x 160. Freehand sections in water mount photographed with transmitted polarized light. FIGS.3 and 4. Spikelets. Fig. 3. Festuca occidentalis. x6.5. Fig. 4. Festuca idahoensis var. idahoensis. x 5 . Dry mounted on glass slides, photographed with incident light.


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FIG.9. Festuca occidentalis. Syntype (in GH). FIG. 10. Festuca idahoensis. Holotype (in DS) isotypes. Specimens collected by Dr. Scouler or Douglas would qualify as syntypes. A second specimen in GH is a ~ossiblesyntype (collected at Fort Vancouver), but label data do not connect it to either Dr. Scouler or Douglas.

Results and conclusions Festuca occidentalis and F. idahoensis differ from each other in leaf structure, panicle structure, spikelet

length, glume length, lemma length, lemma scabrosity, awn length, anther length, and ovary vestiture (Table 1). Piper (1906) has a good line illustration of F. occidentalis; Hitchcock et al. (1969) have good line illustrations of F. idahoensis and F. occidentalis. Photographs of representative leaf cross sections for the two species are given in Figs. 1 and 2; representative spikelets in Figs. 3 and 4; representative ovaries in Figs. 5 and 6; and habits in Figs. 7 and 8.

1. Leaves soft, sharp angled, glossy; lemmas mostly scabrous on upper half, often with awns exceeding them in length; ovaries with densely hispid crowns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F. occidenralis 1. Leaves stiff, round angled, moderately shiny or glaucous; lemmas scabrous only near the tip, with awns not exceeding them in length; ovaries glabrous. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F . idahoensis 2. Leaves involute, hexagonal in cross section, usually with 5 nerves; leaf ribs (adaxial side) densely long pubescent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . var. idahoensis 2. Leaves obovate-pyriform in cross section, with margins tending to open, usually with 7 nerves; leaf ribs (adaxial side) lightly scabrous to sparsely short pubescent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .var. roemeri Pavlick

FIGS.5 and 6. Ovaries. Fig. 5. Festuca occidentalis. x.55. Fig. 6 . Festuca idahoensis var. idahoensis. X.55. Dry mounted, photographed with transmitted polarized light. FIGS.7 and 8. Habit. Fig. 7. Festuca occidentalis (Eastham s.n., 5 July 1942, Rossland, B.C. In V). Fig. 8. Festuca idahoensis var. idahoensis (Brayshaw & Pavlick 77-348, Snehumption Creek, B.C. In V). Specimens mounted on standard herbarium sheets.


TABLE2. Comparison of the type specimens of Festuca ovina v a . ingrata, F. ovina var. oregona, F. idahoensis, and F. occidentalis. Leaf data are taken from basal leaves except for F . occidentalis; leaf data for F. occidentalis syntype were taken from culm leaves owing to lack of basal leaves on thz specimen and are therefore not strictly comparable

F. ovina var. ingrata, Howell 23

F. ovina var. oregona, Cusick 753

F. idahoensis, Abrams 688

Leaf diameter, midlength, mm Leaf cross section shape, midlength

Plicate, hexagonal

Plicate, hexagonal

Plicate, hexagonal*

Leaf vestiture, abaxial surface Culm height, cm Panicle length, cm Panicle width (as pressed), cm Panicle shape (as pressed) Panicle branch flexibility Spikelet length, mm Lower glume length, mm Upper glume length, mm &&a length, mm Lemma scabrosity

Villose 46 9 1.5 Ovate-lanceolate ?stiff 10.5 3.6 5.3 7.4 Scabrous near tip

Scabrous 34 8 2.5 Ovate astiff 10.1 3.4 5.3 7.2 Scabrous near tip

Scaberulous* >781 10.5 1.5 Lanceolate &stiff 12.0 3.2 4.7 6.4 Scabrous near tip

Lemma awn length (maximum), mm Anther length, mm *Leaf data are from a detached basal shoot on Abrarns 688 herbarium sheet. iCulrn is detached so absolute height not known.

F. occidentalis, Douglas s.n. Plains of the Columbia

Irregular hexagon, keel elongate, sharp angled Minutely scaberulous >661 15.5 3.0 Ovate Flexible 7.0 1.9 2.6 4.7 Very scabrous on upper half


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FIG. 11. Distribution of F. occidentalis and F . idahoensis in British Columbia and western Alberta.

The syntype (in GH) of F . occidentalis is typical of the species and is representative of material from western Canada (Fig. 9). The holotypes of F . ovina varieties ingrata and oregona and F . idahoensis are all, within reasonable variation, conspecific with F. idahoensis as is generally recognized (Pavlick 1982) (Fig. 10). A comparison of these types is given in Table 2. Hitchcock et al. (1969) expressed that it was probable that F . idahoensis hydridizes with F . occidentalis and cited a collection which they thought to be intermediate between the two. I have searched WTU (where Hitchcock did this work) for this collection but could not locate it. I have seen no evidence of intermediates in this study. Whether such hybridization takes place, F . occidentalis and F . idahoensis are morphologically well marked and distinct from each other. Festuca occidentalis and F. idahoensis occupy different ecological niches. This is particularly obvious when the two are found in close proximity, as on Buck Hill, near Sooke, Vancouver Island and Newcastle

Island (of the Gulf Islands). At both these stations F. occidentalis was restricted to Pseudotsuga menziesii forests having well-spaced trees, whereas F . idahoensis was found exclusively on adjacent open grass balds. In British Columbia F . idahoensis is restricted mainly to open grasslands in the major valleys (extending to subalpine at some stations) of the interior dry zones, e.g., Okanagan-Similkameen, South ThompsonNicola, Columbia, east Kootenay; and to grass balds on low mountains and hills on southeastern Vancouver Island and Gulf Islands (Pavlick 1982) (Fig. 11). It is not found in the driest grasslands of the arid valley bottoms of the interior but rather on the less arid valley sides (see also Daubenmire (1970) and Franklin and Dryness (1973)). Its distribution coincides with the distribution of suitable grasslands and open areas in dry forests bordering these grasslands. Festuca occidentalis is a more mesic species than F . idahoensis, always occurring in forested areas. In British Columbia it is found on Vancouver Island,


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Queen Charlotte Islands, Lower Fraser Valley, eastern Cariboo District (Fraser Plateau, Quesnel Highland), Nechako Plateau, etc. (Fig. 11). It occurs in open forests and glades, always in at least partial shade (based o n my field observations and herbarium specimens having adequate collection site information). In the southern part of British Columbia it is often associated with Pseudotsuga menziesii. In the north it is found with Pinus contorta, Populus tremuloides, Picea, etc. Its range in British Columbia is much greater than that of F. idahoensis (Fig. l l ) , being widespread in forested areas. O n the basis of these differences in morphology, ecology, and distribution I conclude that F. occidentalis and F . idahoensis are very dissimilar and are best treated as separate species.

Acknowledgments The photographs for Figs. 1-6 were taken by M. L. Florian, B .C. Provincial Museum. ABRAMS,L. 1923. An illustrated flora of the Pacific states. Vol. 1. Ophioglossaceae to Aristolochiaceae. Stanford University Press, Stanford. BEAL,W. J. 1896. Grasses of North America for farmers and students. Vol. 2. Henry Holt & Co., New York. BOIVIN,B. 1967. Enumeration des plants du Canada. VI. Monopsides (2e partie). Nat. Can. (Que.), 94: 471-528. 1979. Flora of the prairie provinces. Part 4. Cyperaceae. Provancheria 5. Phytologia, 43(1): 1-106. CRONQUIST, A., A. H. HOLMGREN, N. H. HOLMGREN, J. L. REVEAL,and P. HOLMGREN. 1977. Intermountain flora. Vascular plants of the Intermountain West, U.S.A. Vol. 6. The Monocotyledons. Columbia University Press, New York. DAUBENMIRE, R. 1970. Steppe vegetation of Washington. Wash. Agric. Exp. Stn. Tech. Bull. 62.

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ELMER,A. D. E. 1903. New western plants. Bot. Gaz. (Chicago), 36: 52-61. FRANKLIN, J . F., and C. T. DYRNESS. 1973. Natural vegetation of Oregon and Washington. USDA For. Serv. Gen. Tech. Rep. PNW-8. FREDERIKSEN, S. 1981. Festuca vivipara (Poaceae) in the North Atlantic area. Nord. J. Bot. 1: 277-292. HITCHCOCK, A. S. 1951. Manual of the grasses of the United States. Revised by A. Chase. U.S. Dep. Agric., Misc. Publ. 200: 1-1051. HITCHCOCK, C. L., A. CRONQUIST, M. OWNBEY, and J. W. THOMPSON. 1969. Vascular plants of the Pacific northwest. Part I. Vascular cryptograms, gymnosperms and monocotyledons. University of Washington Press, Seattle. HOOKER, W. J. 1840. FloraBoreali-Americana. Vol. 2. Henry G. Bohn, London. LOOMAN,J., and K. F. BEST. 1979. Budd's flora of the Canadian Prairie Provinces. Agric. Can. Publ. 1662. Ottawa. MACOUN,J . 1888. Catalogue of Canadian plants. Part 4. Endogens. Geological and Natural History Society of Canada, Ottawa. Moss, E. H. 1959. Flora of Alberta. University of Toronto Press, Toronto. PAVLICK,L. E. 1982. The taxonomy and distribution of Festuca idahoensis in British Columbia and northwestern Washington. Can. J. Bot. 61: This issue. PECK,M. E. 1941. A manual of the higher plants of Oregon. Binfords & Mort, Publishers, Portland, OR. PIPER, C. V. 1906. North American species of Festuca. Contrib. U.S. Natl. Herb. 10: 1-51. SCOGGAN, H. J. 1978. The Flora of Canada. Part 2. National Museums of Canada, Ottawa. pp. 93-545. ST.-YVES, A. 1925. Contribution a l'etude des Festuca (subgen. Eu-Festuca) de 1'Amerique du Nord et du Mexique. Candollea, 2: 229-3 16. TAYLOR, R. L., and B. MACBRYDE. 1977. Vascular plants of British Columbia. The Botanical Garden, the University of British Columbia. Tech. Bull. 4. The University of British Columbia Press, Vancouver.


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