Puccinellia nutkaensis |
Puccinellia arctica |
|
---|---|---|
Alaska alkali grass, Nootka alkali grass, Pacific alkali grass, puccinellie brillante, shining alkali grass |
arctic alkali grass |
|
Habit | Plants perennial; cespitose, occasionally appearing rhizomatous or stoloniferous after rooting at the nodes of buried stems, not mat-forming. | Plants perennial; cespitose. |
Culms | 10-90 cm, usually erect, sometimes decumbent. |
10-30(40) cm, erect. |
Leaves | usually distributed evenly along the culms; ligules 1-3 mm, obtuse to truncate, entire; blades 1.5-6 mm wide when flat, flat to involute. |
basally concentrated; ligules 0.9-3 mm, acute, obtuse, or truncate, entire, margins decurrent; blades usually flat and 0.5-2.2 mm wide, sometimes involute and 0.2-1.6 mm in diameter. |
Panicles | 5-30 cm, compact to diffuse at maturity, lower branches usually erect to ascending, occasionally spreading to descending, spikelet-bearing from near the base or the spikelets confined to the distal 1/2; pedicels from sparsely to densely scabrous, epidermal cells often tumid. |
3-11 cm, diffuse or contracted at maturity, lowest nodes with (2)3-5 branches, lower branches ascending to horizontal, spikelets usually confined to the distal 2/3; pedicels scabrous, without tumid epidermal cells. |
Spikelets | 3.5-12 mm, with 3-7 florets. |
4.5-7(9.5) mm, with (2)3-6(8) florets. |
Glumes | rounded over the back, veins obscure, apices acute to truncate; lower glumes 1-1.6 mm; upper glumes 2-3 mm; calluses with a few hairs; lemmas (2.2)3-4.5(5) mm, herbaceous, glabrous or sparsely hairy on the proximal 1/2, principally along the veins, backs rounded, 5-veined, veins obscure, not extending to the margins, midveins smooth distally, apical margins uniformly and densely scabrous, apices usually acute to obtuse, sometimes acuminate, entire; palea veins glabrous or with short hairs proximally, scabrous distally; anthers 0.5-1.4 mm. |
rounded over the back, veins distinct or obscure, lateral margins often inrolled, apices acute to obtuse; lower glumes 0.8-2.1(2.5) mm; upper glumes 1.8-3 mm; calluses with a few hairs; lemmas 2.5-3.7 mm, herbaceous or membranous, often translucent, often purplish, hairy, particularly on the bases of the veins, backs rounded, 5-veined, veins obscure to distinct, midveins scabrous or smooth distally, sometimes extending to the apical margin, sometimes excurrent, lateral veins not extending to the margins, lateral margins often inrolled, apical margins often hyaline and yellowish, scabrous, entire or slightly erose, apices acute to obtuse; palea veins glabrous, smooth proximally, scabrous from midlength or just below midlength to the apices; anthers 1.2-2.2 mm. |
2n | = 42, 56. |
= 14. |
Puccinellia nutkaensis |
Puccinellia arctica |
|
Distribution |
AK; CA; OR; WA; BC; MB; NB; NL; NS; NT; NU; ON; QC; YT; Greenland
|
AK; NT; NU; YT; Greenland |
Discussion | Puccinellia nutkaensis grows in coastal habitats of continental North America and Greenland, generally in sand and stones in protected intertidal environments. It is variable in form, ranging from diminutive plants that resemble P. pumila to tall, erect plants, often with dense or open inflorescences, resembling P. nuttalliana. Larger plants on the Pacific coast have been called P. grandis Swallen, and those on the Atlantic coast P. lucida Fernald & Weath., but there are many plants of intermediate stature. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Puccinellia arctica is restricted to the North American arctic, where it grows in silt, clay, and sandy substrates near the coast, and on alkaline, sparsely vegetated soils further inland. As treated here, it includes three entities that are sometimes treated as distinct species: P. arctica sensu stricto, P. poacea T.J. Sørensen, and P. agrostidea T.J. Sørensen. Puccinellia arctica sensu stricto is restricted to the southwestern arctic, P. poacea to the high arctic (Ellesmere and Axel Heiberg islands), and P. agrostidea to the southwestern arctic and possibly also Ellesmere Island. There are no morphological characters known for distinguishing these three entities. The first two may differ from the latter by the relatively frequent presence of small scabrules along the upper lemma midvein, slightly more distinct veins, and frequent yellowish margins to the lemma. The taxonomic validity of these characters was not completely understood at the time this treatment was written, but molecular analyses being conducted as this volume went to press (Consaul et al. [in prep.]) suggest that this group is best represented as a single species, P. arctica. Argus and Pryer (1990) stated that all three entities are rare in Canada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 475. | FNA vol. 24, p. 471. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Poeae > Puccinellia | Poaceae > subfam. Pooideae > tribe Poeae > Puccinellia |
Sibling taxa | ||
Synonyms | P. triflora, P. macra, P. lucida, P. laurentiana, P. kamtschatica var. sublaevis, P. hultenii, P. grandis, P. glabra, P. coarctata | P. poacea, P. agrostidea |
Name authority | (J. Presl) Fernald & Weath. | (Hook.) Fernald & Weath. |
Web links |
|