MADRON˜ O, Vol. 54, No. 1, pp. 86–93, 2007

ANEWPLATANTHERA () FROM YOSEMITE NATIONAL PARK,

ALISON E. L. COLWELL U.S. Geological Survey, Western Ecological Research Center, 5083 Foresta Road, El Portal, CA 95318 CHARLES J. SHEVIAK1 Research & Collections, New York State Museum, Albany, NY 12230 PEGGY E. MOORE U.S. Geological Survey, Western Ecological Research Center, 5083 Foresta Road, El Portal, CA 95318

ABSTRACT A new species, yosemitensis Colwell, Sheviak and P. Moore, from Mariposa County, California, is described and illustrated. Endemic to wet montane meadows between the main stem and the South Fork of the Merced River in Yosemite National Park, it is distinct from Platanthera stricta Lindl., P. sparsiflora (S. Wats.) Schlecter, and P. purpurascens (Rydb.) Sheviak & W. F. Jennings based on vegetative habit, floral morphology, color, and fragrance and pollination mechanics. Key Words: California, Orchidaceae, Platanthera, Sierra Nevada, Yosemite National Park.

The central Sierra Nevada of California sup- strongly sweet-spicy-musk scented. 30 July ports a small number of Platanthera species, 2003, A.E.L. Colwell & C. Coulter 03-33. including P. dilatata (Pursh) Lindl. ex Beck var. Holotype: UC 1861834; Isotypes: NYS leucostachys (Lindl.) Luer, P. sparsiflora (S. A33130, YM 117815. Wats.) Schlechter, P. stricta Lindl., and P. Folia 5–7 prope basin caulis plerumque (su- tescamnis Sheviak & Jennings. Platanthera pur- prema infra medium) inserta, supra bracteis purascens (Rydb.) Sheviak & W. F. Jennings was redacta. Folium infimum reflexum, ceterum also reported from the central Sierra Nevada of perascendens, 9–25 3 1.5–3 cm. Spica laxe California (Coleman 1995; Sheviak 2002) based florifera, longitudine 1/2 caulis partes aequantia, on a fragmentary specimen. The range of P. aliquantum glauca. Sepalum dorsale viride vel purpurascens is otherwise limited to the southern margine flavescenti, porrectum. Sepala lateralia Rockies from southernmost Wyoming to south- viride reflexa. Corolla citrina. Labellum rhombi- central New Mexico and eastern Arizona. The lanceolatum, saepe basi plus minusve rotundati- anomalous, disjunct nature of the putative dilatata, apice plerumque apicem sepalii dorsalis California record stimulated our investigation, contingenti, interdum libero, labellum tum hor- which determined that the record was based not izontale, 4–6 mm longum. Calcar saccatum vel on P. purpurascens but rather represented an scrotiforme inflatum e basi tenui. Columna undescribed, endemic species. parvula rotundata, connectivum angustum sed evidens, anthera sacculis parallelis vel aegre DESCRIPTION divergentibus, lobis rostellii brevissimis prope marginem superiorem orificii calcaris terminanti- Platanthera yosemitensis A. Colwell, C. Sheviak bus. Viscidia orbiculati-quadrata. and P. Moore, sp. nov. (Fig. 1). TYPE: USA, Perennial herb, 20–80 cm tall, composed of California, Mariposa County, Yosemite Na- a single stalk from a horizontal tapered tuberoid tional Park, northeast of Badger Pass Ski and a few fleshy roots, the bud for the subsequent Area, 37u399N, 119u399W, 2200 m. Wet year forming near the base of the current year’s meadow with Platanthera dilatata var. leu- stalk on a newly developing tuberoid. Stem stiff costachys Lindley, Platanthera sparsiflora (S. and round with minute longitudinal ridges. Watson) Schltr., Polygonum bistortoides Leaves 5–7 on the lower 2/5 of stem; Lowest leaf Pursh, Gentianopsis simplex (A. Gray) Iltis, reflexed, ca. 4 cm long 3 1 cm wide, the others Mimulus primuloides Benth., Spiranthes ro- short-sheathed, clasping, three-nerved, condupli- manzoffiana Cham. Flowers greenish yellow, cate, lanceolate, strongly ascending, tapering to an acute, naviculate tip, 9–25 cm long, 1.5–3 cm 1 Author for correspondence, e-mail: csheviak@mail. wide, reduced above to clasping bracts. Inflores- nysed.gov cence a lax spike along the upper half of the stem, 2007] COLWELL ET AL.: A NEW PLATANTHERA FROM YOSEMITE 87

FIG.1. Platanthera yosemitensis. A. Habit; B. Side view of flower; C. Detail of inflorescence; D. Root system; E. Dissected view of flower; F. Front view of flower; G. Detail of mature fruit. Illustration by John Myers. 88 MADRON˜ O [Vol. 54 somewhat glaucous on rachis, floral bracts, and September 2004, A.E.L. Colwell & P. Moore 04- flowers. Flowers 30–50, sparsely arranged in an 306 (YM 118100). irregular spiral, floral bracts attenuate, 1-nerved, approximately equaling the ovary. Flowers ses- DISCUSSION sile, resupinate, gradually diminishing in size upwards and the uppermost generally not de- Distribution and Habitat veloping mature fruit. Dorsal sepal green or the margins yellowish, ovate, porrect, partially en- Platanthera yosemitensis is currently known closing and connivent with the petals to form from only nine sites within Yosemite National a hood. Lateral sepals green, oblong, slightly Park, all on the granitic upland south of tapered to tips, reflexed downwards along the Yosemite Valley, within 4 km of Monroe Mea- sides of the ovary. Corolla yellow, the segments dows (Fig. 2). As the range is currently known, it thick, entire. Petals falcate, obliquely dilated at is the only orchid species endemic to the Sierra the base, asymmetrically ovate-deltoid, the up- Nevada in California. Its habitat is wet meadows turned obtuse apices approximate, (3–) 4 mm between 2100 and 2285 m elevation in partial long. Lip rhombic-lanceolate, the base often shade cast by a surrounding forest of Abies somewhat rounded-dilated, the apex commonly magnifica Andr. Murray and Pinus contorta connivent with the apex of the dorsal sepal, Loudon. These meadows are at headwaters of sometimes free and the lip then horizontal but first order streams in steep terrain with forested not descending, (4–) 6 mm long. Spur saccate or watershed above them. Platanthera yosemitensis scrotiform, expanding from a more slender base, occurs within these meadows in sites of active (2.0–) 2.8 mm long. Column very small, rounded, groundwater seepage. Individuals are found in the anther erect, connective narrow but evident, well-developed turf with dense (,1 m tall) anther sacs parallel to slightly diverging, rostel- herbaceous vegetation, often dominated by lum lobes very short, obscure, the orbicular- Carex utriculata Boott, Dodecatheon alpinum quadrate viscidia held above the orifice of the (A. Gray) E. Greene, Eleocharis pauciflora spur. Fruit a stout cylindric capsule, 1 cm long in (Light.) Link, Luzula subcongesta (S. Watson) lowest flowers, diminishing in size upwards to Jepson, Pedicularis attolens A. Gray, Perideridia 0.3 cm. Perianth persistent on the capsule apex bolanderi (A. Gray) Nelson & J. F. Macbr., but shriveling and darkening upon drying. Phalacroseris bolanderi A. Gray, and Polygonum Chromosome number. 2n 5 42 (C. Sheviak, bistortoides. A.E.L. Colwell, & A. Sanders 6998 [NYS The upland area south of Yosemite Valley A33490], from 3 inflorescences collected at same inhabited by P. yosemitensis is noteworthy site as A.E. L. Colwell & C. Coulter 03-33). because it contains several species endemic to the central and southern Sierra Nevada: Allium Flowering period. July–August. yosemitense Eastw., Eriophyllum nubigenum A. Gray, Hulsea brevifolia A. Gray, Ivesia unguicu- Etymology. This species is named for Yosemite lata A. Gray, Senecio clarkianus A. Gray, National Park, to which it appears to be endemic Phalacroseris bolanderi,andTrifolium bolanderi (Fig. 2). We suggest the common name Yosemite A. Gray. Age and stability of this montane bog-orchid. habitat and hence of the composition of the Paratypes. USA, California, Mariposa Coun- regional species pool (Millar and Woolfenden ty: Yosemite near Glacier Point, 14 July 1923, 1999) is likely a factor related to this level of George Henry Grinnell s.n. (RSA 382940); Mead- endemism. This upland remained largely free of ow above Chinquapin on road to Glacier Point, ice during the most recent glacial events that 14 July 1923, George Henry Grinnell 123 (RSA scoured much of the Sierra Nevada and carved 382932); Badger Pass, Yosemite National Park, the valleys to the north and south in the last two Mary V. Hood, s.n. 6 August 1965 (YM 117456); million years (Matthes 1930; Alpha et al. 1987). Yosemite National Park, off Glacier Point Road, Matthes (1930) infers that, during periods of 14 Jul 1993, R.A. Coleman s.n. (NYS A12358); glacial maxima, this exposed surface was not Yosemite National Park, Meadow Brook, 37u forested, but was instead covered by an alpine 419N, 119u399W, 2158 m, 24 July 2003, A.E.L. meadow that had seasonal snow cover as the area Colwell & C. Coulter 03-22 (YM 117810); does currently. The current habitat of P. yosemi- Yosemite National Park, Meadow Brook, tensis is similar to the habitat described by 37u419N, 119u399W, 2158 m, 20 August 2003, Matthes and to modern day periglacial environ- A.E.L. Colwell & C. Coulter 03-46 (YM 117804); ments. Yosemite National Park, Meadow near Glacier In addition to harboring glacial refugia during Point Road, 37u399N, 119u399W, 2225 m, 13 the Pleistocene, recent geologic evidence suggests August 2004, A.E.L. Colwell & A. Sanders 04- that montane habitat in the Sierra Nevada is 238 (MO 04479050); Yosemite National Park, significantly older (Small and Anderson 1995; Rail Creek, 37u399N, 119u409W, 2200 m, 26 Wernicke et al. 1996; Stock et al. 2004, 2005; 2007] COLWELL ET AL.: A NEW PLATANTHERA FROM YOSEMITE 89

FIG. 2. Range of P. yosemitensis in Yosemite National Park, central Sierra Nevada, California.

Mulch et al. 2006), than the few million years millions of years in age should be thought of as previously accepted (Sharsmith 1940; Chabot and a site of in situ speciation of montane Billings 1972; Raven and Axelrod 1978). House et (Kimball et al. 2004). In this context, the al. (1998, 2001) propose a Cretaceous origin of discovery of a distinct orchid species is not high elevation mountains in the southern Sierra surprising and the distribution of P. yosemitensis Nevada. Stock et al. (2005) present evidence that may well be more widespread within this region some Sierra Nevada uplands have been eroding than is currently known. It should therefore be very slowly, only about 10 m per million years. sought in similarly unglaciated wet meadow sites Stable montane habitat on the order of tens of elsewhere in the central Sierra Nevada. 90 MADRON˜ O [Vol. 54

Taxon Relationships (L.) R. Br., but subsequently it was largely ignored, even in synonymy, until treated as The Platanthera species of the central Sierra avarietyofPlatanthera hyperborea (L.) Lindl. Nevada of California include P. dilatata var. by Luer (1975). In the intervening years it had leucostachys, P. sparsiflora, P. stricta,andP. been confused with P. stricta Lindl., with which it tescamnis. They are part of a transcontinental shares a short, scrotiform or saccate to inflated- complex of species long noted for taxonomic clavate spur. This single-character is intractability. They are not readily determined by analogous to the recognition of P. sparsiflora superficial examination of gross morphology, but based on its large column; in both cases, the rather require careful study of certain critical character reflects a pollination syndrome and is characters, especially of the column. a reliable indicator of neither evolutionary Platanthera sparsiflora has typically been history nor relationship (Sheviak 2002). Of recognized on the basis of a large column filling greater significance is the similar vegetative habit much of the hood formed by the sepals and of P. stricta and P. purpurascens. The leaves of petals. More significantly, the viscidia, the sticky both species are relatively short, blunt, commonly pads that affix the pollinaria to the pollinator, are widely spaced, and abruptly diverging from the borne on prominent, angular rostellum lobes that stem, often at nearly 90 degrees. Plants of both present them forward and to either side of, or species are commonly slender, with long, lax somewhat below, the orifice of the spur. The inflorescences, but robust plants can be more connective, the sterile tissue between the anther densely flowered. However, the two species differ sacs, is correspondingly very broad. The column significantly in other details, most significantly in is typical of those of Platanthera species that column shape and floral fragrance, and less place pollinaria on insects’ eyes. This configura- definitively in flower color and lip shape. In the tion is seen in the types of P. sparsiflora and its column of P. stricta, the anther sacs and taxonomic synonyms, Limnorchis laxiflora rostellum lobes are approximately parallel or Rydb., Limnorchis ensifolia Rydb., and Habe- somewhat converging. In contrast, in P. purpur- naria aggregata Howell (See Sheviak & Jennings ascens they are wide-spreading. Flowers of P. [2006] for discussion and illustration of types.). stricta are scentless or rarely with the faintest hint The more eastern P. zothecina (Higgins & Welsh) of a spicy scent; those of P. purpurascens are Kartesz & Gandhi, of the Plateau, strongly musty scented. These two characters bears a functionally similar column, but it is not evidently reflect different pollination specializa- clear if it reflects a common origin or a parallel or tions that would be of species-level significance. convergent development. Additionally, flowers of P. stricta are typically In contrast to the broad, angular-lobed column a concolor medium green, with linear oblong lip of P. sparsiflora, the columns of the other species of the same hue as the rest of the flower. The lip in the region are small, with abbreviated, more may vary occasionally toward more lanceolate rounded rostellum lobes that present the viscidia and, in the North, yellowish, but the species is closer to the orifice of the spur, typically near the much more uniform than is P. purpurascens.InP. upper margin. Pollinaria are thus placed on the purpurascens, populations commonly show con- proboscis or mandibles or on the eyes of smaller siderable variation with lip linear lanceolate to insects. Among these species, P. dilatata var. broadly rounded-dilated at the base, and varying leucostachys is distinguished by its pure white, in color from markedly bluish green to dull nocturnally fragrant flowers with slender spurs yellowish; sometimes it is marked with reddish much longer than the lips. The remaining species blotches, hence the specific epithet. bear flowers more or less green or greenish yellow Platanthera yosemitensis differs from P. stricta in general aspect. These include the recently and P. purpurascens, the other species with described P. tescamnis which is discussed at scrotiform-saccate spurs, in vegetative habit. In length by Sheviak & Jennings (2006). For contrast to the wide spacing and typically abrupt purposes of the present discussion, P. tescamnis spreading of the rather short, blunt leaves of P. is recognized by a slender to slightly clavate spur stricta and P. purpurascens, those of P. yosemi- somewhat shorter to slightly longer than the lip. tensis are long, tapered, ascending, and clustered The remaining species bear comparatively short, at the base of the stem. The long, lax in- inflated spurs. florescence is then borne on a sparsely-bracted Platanthera purpurascens was recently reported scape. from the central Sierra Nevada of California Flowers of P. yosemitensis and P. purpurascens (Coleman 1995; Sheviak 2002) based on a de- show limited similarity. In addition to the spurs, termination by Sheviak of an inflorescence the lanceolate lip, and orbicular to orbicular- fragment. This species was originally described quadrate viscidia characteristic of P. yosemitensis over a century ago as one of Rydberg’s species of are typically, if not uniformly, seen also in P. Limnorchis (Rydberg 1901). Ames (1910) reduced purpurascens. A dilation of the base of the lip is it to varietal status under Habenaria hyperborea common in P. yosemitensis, and is sometimes 2007] COLWELL ET AL.: A NEW PLATANTHERA FROM YOSEMITE 91 found in P. purpurascens, where it is much less tions. Although its limited distribution might be common, but may be more strongly developed. taken to explain its greatly limited variability, in Otherwise, the species differ markedly. other Platanthera, especially P. purpurascens, The rachis, floral bracts, pedicillate ovary, and great variability is commonly seen within even abaxial surfaces of the sepals of P. yosemitensis small colonies. are somewhat glaucous, a condition unique in the Hybrid formation in Platanthera is frequently genus. Only the very large-flowered P. zothecina reported, and is suspected between P. yosemiten- of the Colorado Plateau is superficially similar in sis and sympatric species. Platanthera sparsiflora the whitish-green cast of its inflorescence. In that and P. dilatata var. leucostachys are common in species, however, the whitish coloring is not so the same meadows in which P. yosemitensis is much a glaucous bloom as a general pale found. A single in each of two P. coloration. Perhaps as a consequence of this yosemitensis populations appears to have floral glaucous surface, flowers of P. yosemitensis characters intermediate between P. yosemitensis persist in a blackened, shriveled state atop the and P. sparsiflora. Phenology provides some expanded capsules, lending a distinctive aspect to measure of isolation as P. sparsiflora blooms the plant after flowering. earlier and is generally in fruit set by the time P. Platanthera yosemitensis is furthermore unique yosemitensis plants begin flowering. Further- in its concolor rich yellow corolla. In other more, the different column structures and result- species with yellowish lips, the hue is more ing differences in placement of pollinaria suggest suffused with green or rather dull, and the petals that such crosses must be very rare and are are green or greenish. The clear color throughout probably the result of exploration by generalist the corolla in P. yosemitensis is notable. The pollinators rather than a properly oriented scrotiform-saccate spur is essentially an extreme vector. Similarly, two plants at one site were development of the inflated-clavate form seen intermediate in color and morphology between P. occasionally in P. stricta and P. purpurascens, yosemitensis and P. dilatata var. leucostachys. pendulously inflated from a short slender base. Hybridization between these species again would Whereas saccate spurs in P. stricta and P. appear to be rare due to the totally incompatible purpurascens are more nearly sessile on the base spur lengths. Nonetheless, random visitation by of the lip, and the more clavate extreme is merely non-adapted insects might more frequently result a blunt inflation of a generally tubular structure, in hybridization of these species than of P. in P. yosemitensis the nearly spherical sac is born yosemitensis with P. sparsiflora because the on the summit of a distinct expanding tube. columns of P. yosemitensis and P. dilatata are Platanthera yosemitensis has a pronounced similarly proportioned. fragrance with a prominent musk component. It Platanthera dilatata var. leucostachys and P. has been likened by different observers to a corral sparsiflora often fill all the fruits on their of horses, asafœtida, strong cheese, human feet, inflorescences. In contrast, P. yosemitensis gen- sweaty clothing, or simply disagreeable. It is erally matures only the fruits on the lower two- similar to the scent of Polygonum bistortoides, thirds of the inflorescence. A few individuals have a frequent component of the meadows P. been found with all fruits filled, but others, yosemitensis inhabits. Other similar species vary especially those in small populations or on the from strongly spicy of (P. dilatata vars. margin of a population, fill only one or two fruits dilatata and leucostachys), sweetly pungent (P. on an inflorescence. When this is the case, the dilatata var. albiflora (Cham.) Ledeb., P. hur- filled fruits are not necessarily the lowest fruits, or onensis (Nutt.) Lindl., most P. tescamnis,someP. even adjacent to each other on the inflorescence aquilonis, etc.), or strongly musty (P. purpuras- stalk, implying that this species is not self- cens), to entirely or virtually scentless (P. stricta, pollinating. P. sparsiflora; Coleman’s report [Coleman 1988] Conservation Status of a sweet scent in the latter was the result of an editing error, [Coleman pers. com.]). The combi- All of the known occurrences of P. yosemiten- nation of scent, the yellow color and the short sis are within the boundaries of Yosemite distance between the viscidia (0.3 mm) in P. National Park. It is likely that additional yosemitensis may be indicative of a mosquito or occurrences will be found in the vicinity, espe- fly pollination syndrome, which is also reported cially to the south. Of nine known occurrences, from the much larger-flowered P. obtusata (Raup five are located in remote areas, while four are 1930; Stoutamire 1968; Thien 1969; Gorham adjacent to areas of frequent human use. The 1976). delicate inflorescence of this species is difficult to Platanthera yosemitensis is consistent in vege- discern in the dense meadow vegetation in which tative and floral morphology, floral color, and it grows, which makes P. yosemitensis less likely scent, displaying only limited variation. One to be noticed or poached. A greater concern is the feature of P. yosemitensis is its uniformity of small number of individuals at most of the sites character expression within and between popula- (at four sites, fewer than ten flowering individuals 92 MADRON˜ O [Vol. 54

have been observed), which are at risk of extirpation due to random natural events as well as anthropogenic threats. In order to protect

lip length these populations, location details have been left

3 out of the specimens cited above. All of the known sites are in meadows exhibiting encroach- ment by Pinus contorta, a regional phenomenon in the central Sierra Nevada (Millar et al. 2004), elliptic arching, internodes obscured which may pose a long-term threat to these trong musk Less than 0.5 Yellow Lance-elliptic to linear Ascending to gradually populations. Active management may thus even- tually be required to insure the species’ survival. The similarity of early season vegetative growth of the three sympatric Platanthera species inYosemiterenderssurveysforthisplant effective only from July to September when the

lip length plants are in flower or fruit. rorifice Abovespurorifice 3

KEY TO THE CALIFORNIA PLATANTHERA SPECIES icular or oblong Orbicular-quadrate (much less in some scentless plants) yellow to yellowish) elliptic arching, internodes obscured 1. Flower white to cream; spur 1.53 or more the 0.8 to 1.4 Green (lip greenish Lance-elliptic to linear Ascending to gradually length of the lip, slender, cylindric ...... P. dilatata var. leucostachys 19 Flower green to yellow, spur slightly longer to to

iform Clavulate (cylindric) Scrotiform much shorter than lip; cylindric to variously 3 inflated

lip length 2. Viscidia presented on rostellum lobes to

3 either side of spur orifice; column propor- tionally large, occupying about 2/3 of the hood formed by the dorsal sepal and petals, the connective very broad, the rostellum lobes prominent, widely spaced, less than 1 marked with small areas of fine reddish venation) ovate-lanceolate internodes exposed and together with the stigma and connec- Approximately 0.25 Oblong to Abruptly spreading, tive forming a hemispherical chamber...... P. sparsiflora 29 Viscidia presented on rostellum lobes above lip spur orifice; column proportionally small, 3

to occupying less than half of the hood formed .

3 by the dorsal sepal and petals, the connec- tive narrow, the rostellum lobes scarcely elevated, parallel, diverging, or converging, SPECIES at most separated by a narrow slit and not forming a hemispherical chamber 3. Leaves oblong to ovate-lanceolate, approximately 1.5 length elliptic arching, internodes obscured or abruptly spreading, internodes exposed widely spaced along stalk, abruptly Approximately 1 Lance-elliptic to linear Ascending to gradually spreading from base to somewhat ascending, with internodes exposed LATANTHERA

P and clearly evident; spur club-shaped to scrotiform; lip green (sometimes marked with small areas of fine

lip reddish venation); scentless. . . . . P. stricta

3 39 Leaves lance-elliptic to linear elliptic, ALIFORNIA clustered at base of stalk, ascending to C leucostachys P. sparsiflora P. stricta P. tescamnisgradually P. yosemitensis arching from base, with

var long-sheathing leaf bases mostly ob- scuring internodes; spur slender to scrotiform; lip yellowish; pungent- length elliptic arching, internodes obscured scented

Above spur orifice Either side of spur orifice Above spur orifice Above spu 4. Spur ,0.5 3 lip length; saccate to

P. dilatata scrotiform; lip bright yellow, in- florescence glaucous; pungent

HARACTERS OF THE musk scent ...... P. yosemitensis 49 Spur 0.8 to 1.4 3 lip length;

1. C clavulate (-cylindric); lip greenish yellow, inflorescence not glaucous; Species

placement sweet pungent scent or scentless . . ABLE T Spur shapeSpur length SlenderFlower to color cylindric Greater than 1.5 WhiteScentViscidia Slender to cylindricViscidia shapeLeaf shape Linear to Strong linear-oblong Club-shaped spicy to scrot Lance-elliptic to linear Orbicular Green to oblong Orbicular None Green (lip sometimes Orb None (rarely faintly spicy) Sweet pungent or none S Leaf orientation Ascending to gradually ...... P. tescamnis 2007] COLWELL ET AL.: A NEW PLATANTHERA FROM YOSEMITE 93

ACKNOWLEDGMENTS Transactions of the 64th North American Wildlife and Natural Resources Conference. Wildlife Man- We wish to thank Dean Wm. Taylor for initially agement Institute, Washington D.C. bringing this taxon to our attention and for comments ———, R. D. WESTFALL,D.L.DELANY,J.C.KING, on the manuscript. Ronald Coleman and Doug Gold- AND L. J. GRAUMLICH. 2004. Response of sub- man also provided helpful comments. Angela Sanders, Charlotte Coulter, Cathy Sheehe, and Andrew Cham- alpine conifers in the Sierra Nevada, California, bers assisted with field work. We would also like to USA., to 20th-century warming and decadal thank the staff of the following herbaria for use of their climate variability. Arctic, Antarctic and Alpine facilities or for providing specimen information: CAS, Research 36:181–200. DAV, FSC, GH, RSA, SJSU, UC, US, YM and YU. MULCH, A., S. A. GRAHAM, AND C. PAGE CHAMBER- This work was supported in part by the National Park LAIN. 2006. Hydrogen isotopes in Eocene river Service Inventory and Monitoring Program. gravels and paleoelevation of the Sierra Nevada. Science 313:87–89. LITERATURE CITED RAUP, H. M. 1930. The pollinization of Habenaria obtusata. Rhodora 32:88–89. ALPHA, T. R., C. WAHRHAFTIG, AND N. KING HUBER. RAVEN,P.H.AND D. I. AXELROD. 1978. Origin and 1987. Oblique map showing maximum extent of relationships of the California flora. University of 20,000-year-old (Tioga) glaciers, Yosemite Nation- California Publications in Botany 72:1–134. al Park, Central Sierra Nevada, California. Mis- RYDBERG, P. A. 1901. The American species of cellaneous Investigations Series Map I-1885. U.S. Limnorchis and Piperia, north of Mexico. Bulletin Geological Survey, Reston, VA. Torrey Botanical Club 28:605–643. AMES, O. 1910. The genus Habenaria in North SHARSMITH, C. W. 1940. A contribution to the history America. Orchidaceae: Illustrations and Studies of of the alpine flora of the Sierra Nevada. Ph.D. the Family Orchidaceae. Fascicle IV. The Merry- dissertation. University of California, Berkeley, mount Press, Boston, MA. CA. CHABOT,B.F.AND W. D. BILLINGS. 1972. Origins and SHEVIAK, C. J. 2002. Plantanthera. Pp. 551–571 in Flora ecology of the Sierran alpine flora and vegetation. of North America Editorial Committee (eds.) Flora Ecological Monographs 42:163–199. of North America, volume 26, Magnoliophyta: COLEMAN, R. A. 1995. The wild orchids of California. Liliidae: Liliales and Orchidales. Oxford University Cornell University Press, Ithaca, NY. Press, New York, NY. ———. 1988. The orchids of Yosemite National Park. ——— AND W. F. JENNINGS. 2006. A new Platanthera American Orchid Society Bulletin 57(6):609–623. from the intermountain west. Rhodora 108:19–31. GORHAM, J. R. 1976. Orchid pollination by Aedes mosquitoes in . The American Midland SMALL,E.E.AND R. S. ANDERSON. 1995. Geomor- Naturalist 95:208–210. phically driven Late Cenozoic rock uplift in the Sierra Nevada, California. Science 270:277–280. HOUSE, M. A., B. P. WERNIKE, AND K. A. FARLEY. 1998. Dating topography of the Sierra Nevada, STOCK, G. M., R. S. ANDERSON, AND R. C. FINKEL. California, using apatite (U-Th)/He ages. Nature 2004. Pace of landscape evolution in the Sierra 396:66–69. Nevada, California, revealed by cosmogenic dating ———, ———, AND ———. 2001. Paleo-geomorphol- of cave sediments. Geology 32(3):193–196. ogy of the Sierra Nevada, California, from (U-Th)/ ———, ———, AND ———. 2005. Rates of erosion He ages in apatite. American Journal of Science and topographic evolution of the Sierra Nevada, 26 10 301:77–102. California, inferred from cosmogenic Al and Be KIMBALL, S., P. WILSON, AND J. CROWTHER. 2004. concentrations. Earth Surface Processes and Land- Local ecology and geographic ranges of plants in forms 30:985–1006. the Bishop Creek watershed of the eastern Sierra STOUTAMIRE, W. P. 1968. Mosquito pollination of Nevada, California, USA. Journal of Biogeogra- Habenaria obtusata (Orchidaceae). Michigan Bot- phy 31:1637–1657. anist 7:203–212. LUER, C. A. 1975. The native orchids of the United THIEN, L. B. 1969. Mosquito pollination of Habenaria States and Canada, excluding Florida. The New obtusata (Orchidaceae). American Journal of Bot- York Botanical Garden, Bronx, NY. any 56:232–237. MATTHES, F. E. 1930. Geologic history of the Yosemite WERNICKE, B., R. CLAYTON,M.DUCEA,C.H.JONES, Valley. Professional Paper P-0160. U.S. Geological S. PARK,S.RUPPERT,J.SALEEBY,J.K.SNOW,L. Survey, Reston, VA. SQUIRES,M.FLIEDNER,G.JIRACEK,R.KELLER, MILLAR,C.I.AND W. B. WOOLFENDEN. 1999. Sierra S. KLEMPERER,J.LUETGERT,P.MALIN,K. Nevada Forests: Where did they come from? MILLER,W.MOONEY,H.OLIVER, AND R. Where are they going? What does it mean? Natural PHINNEY. 1996. Origin of high mountains in the resource management: perceptions and realities. continents: the southern Sierra Nevada. Science Pp. 206–236 in R. McCabe and S. Loos (eds.), 271:190–193.