Dupontia fisheri

R. Br.
Common names: Fisher's tundragrass Dupontie de fisher
Treatment appears in FNA Volume 24. Treatment on page 604.

Rhizomes 1-3 mm thick. Culms 5-80 cm, erect, glabrous. Ligules of lower leaves 0.4-3 mm; ligules of flag leaves 1-4 (5.5) mm, usually lacerate; blades 1-13 cm long, 1-4 mm wide. Panicles 2.5-18 cm long, 1-6 cm wide. Spikelets 4-8.5 (9) mm; rachilla internodes 1-1.5 mm. Glumes 4-8.5 (9) mm; lemmas 3-6.5 mm; paleas 2.8-6 mm; anthers 1.5-3.5 mm. Caryopses 1.5-3 mm. 2n = 42, 44, 66, 84, 88, about 105, about 126, 132.

Distribution

Greenland, Nfld. and Labr. (Nfld.), Man., N.W.T., Nunavut, Ont., Que., Yukon, Alaska

Discussion

Dupontia fisheri grows in wet meadows, wet tundra, marshes, and along streams and the edges of lagoons, ponds, and lake shores, in sand, silt, clay, moss, and rarely in bogs.

Two subspecies of Dupontia are sometimes recognized in North America. Dupontia fisheri R. Br. subsp. fisheri supposedly differs from subsp. psilosantha (Rupr.) Hulten in being shorter than 40 cm, having erect panicle branches, 2-4 florets per spikelet, pubescent, obtuse lemmas, and 2n= 84, 88, or 132. Dupontia fisheri subsp. psilosantha is taller, has reflexed panicle branches, 1-2 florets per spikelet, more or less glabrous, acute lemmas, and 2n =42 or 44. Plants referable to subsp. psilosantha are restricted to coastal marshes, rarely penetrating inland along riparian habitats, from James Bay to the lower arctic archipelago. Plants referable to subsp. fisheri are less halophytic and more northerly in their distribution, being found in a variety of inland marshes and wet tundra habitats from northern Alaska to Ellesmere Island. Intermediates are readily found (e.g., hexaploid, 2N = 66 "hybrids" from Alaska) and the correlations among chromosome number, morphology, ecology, and distribution are relatively weak in North America and Greenland. For these reasons, no subspecific taxa are recognized in this treatment. Dupontia fisheri hybridizes with Poa eminens to form ×Dupoa labradorica (p. 602). The hybrids differ from D. fisheri in having glumes that usually do not exceed the florets, and in having some woolly or crinkly callus hairs. The hybrid genus ×Arctodupontia is formed from D. fisheri and Arctophila fulva, and differs from D. fisheri in having lemmas with truncate, lacerate to dentate apices, rather than acute to acuminate apices.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Dupontia fisheri"
132 +, 126 +, 105 +, 88 +, 84 +, 66 +, 44 +  and 42 +
membranous +  and scarious +
pubescent +  and scabrous +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
acute +  and acuminate +
Jacques Cayouette +  and Stephen J. Darbyshire +
R. Br. +
1 (?) +  and 3 (?) +
2.2 cm22 mm <br />0.022 m <br /> (?) +
straight +
basal +  and terminal +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
1 cm10 mm <br />0.01 m <br /> (13 cm130 mm <br />0.13 m <br />) +
not evident +
folded +  and flat +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
8.5 cm85 mm <br />0.085 m <br /> (?) +
erect;reflexed +
spikelike +
0.7 cm7 mm <br />0.007 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
hairy +  and glabrous +
Fisher's tundragrass +  and Dupontie de fisher +
not branching +
5 cm50 mm <br />0.05 m <br /> (80 cm800 mm <br />0.8 m <br />) +
not woody +
Greenland +, Nfld. and Labr. (Nfld.) +, Man. +, N.W.T. +, Nunavut +, Ont. +, Que. +, Yukon +  and Alaska +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
1 +  and 4 +
compressed +
reduced +
shorter or longer +
subtending +
obtuse +  and lanceolate-attenuate +
subequal +
0.4 cm4 mm <br />0.004 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
membranous +
usually exceeding the distal florets +  and equaling +
uncinate +
1/6 +  and 1/3 +
1-7(9)-veined +
pubescent +  and glabrous +
ovate +  and ovatelanceolate +
0.3 cm3 mm <br />0.003 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
membranous +  and coriaceous +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
membranous +
inconspicuous +
lanceolate +
concealed +  and prominent +
2 +  and 1 +
well-developed +
2-keeled +
0.28 cm2.8 mm <br />0.0028 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
2.5cm +  and 18cm +
spikelike +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
dry +  and fleshy +
compressed +
0.4 cm4 mm <br />0.004 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Dupontia fisheri +
Dupontia +
species +
membranous +
parallel +  and converging +
aquatic +  and terrestrial +