Grasses Part 9. Grasses of Saline Areas
- Oanh Nguyễn
- 15 hours ago
- 7 min read
by Patsy Cotterill; photos by the author unless otherwise indicated.
Originally published in the 2022 October Issue of the WildFlower News
All of the following grasses were found on the shores of Miquelon or South Cooking Lakes this summer.
Nuttall’s alkaligrass, Nuttall’s salt-meadow grass, Puccinellia nuttalliana
This perennial, summer-flowering grass is tufted but nevertheless can form dense, extensive swards along the shores of shallow lakes that leave saline deposits as the water recedes during summer droughts. The grass grows 30-50 cm tall and has
narrow inrolled leaves and wide-spreading, branched, diffuse panicles 10-20 cm long with a pyramidal shape. The branches are ascending to wide-spreading and are beaded with small, slender, short-stalked spikelets. These are narrow, cylindrical and about 5 mm long, consisting of typically five florets above the tiny glumes, the first glume about 1 mm long and the second about 1.8 mm. The lemmas are ca. 2 mm long, grey-greenish, with indistinct nerves, and a slightly ragged, papery tip. At maturity, the spikelets break up easily above the glumes and between the florets. By late August most plants are straw-like and forming airy masses along shores.
Nuttall’s alkaligrass has a close relative, spreading or European alkaligrass, Puccinellia distans, which can co-occur with P. nuttalliana along shores, but true to its non-native nature (it is a circumboreal species but likely introduced to Canada) it favours more anthropogenic habitats, such as roadside puddles (where road salting has occurred), gravel pits, shallow ditches and other disturbed, somewhat saline areas. It is a more compact-tufted, shorter plant than P. nuttalliana with flat, broader leaf blades (2-4 mm) and a more obvious bluish or purplish hue to the panicle. The lower panicle branches eventually become deflexed. Other differences include rounded glumes (versus keeled in P. nuttalliana), the ovate lemmas slightly smaller at 1.5-2mm, and with a rounded or cut-off tip, and smaller (less than 1 mm long) anthers. The common name “spreading” does not appear to be apt, as this species does not form the extensive airy biomass of Nuttall’s alkaligrass.
Both species are widely distributed in North America, with P. nuttalliana most common across Canada and in the west and central U.S. Interestingly, of the five species of Puccinellia included in the (1983) Flora of Alberta, only two remain. One species (P. cusickii) is now included in P. nuttalliana and P. hauptiana is not considered distinct from P. distans. (Sometimes taxonomic changes do make life simpler!) The fifth species, a puzzling taxon once also considered to be a Glyceria, P. pauciflora, has now been transferred to a different genus altogether, Torreyochloa.
Puccinellia maritima is a major saltmarsh grass of Europe. It has been introduced to Quebec and some Maritime provinces, as well as Greenland and some northeast coastal American states. Tolerance to high pH is the hallmark of the genus.
Common reed, Phragmites australis
American reed, Phragmites australis subsp. americanus
European reed, Phragmites australis subsp. australis
This grass comes in two subspecies, native (American reed, subsp. americanus) and non-native (European reed, subsp. australis) and distinguishing between them is important. According to the Canadensys Vascan database European reed is “doubtfully” present in Alberta, but because it exists in B.C. and provinces to the east it is worth being on the lookout for.
The species is a strikingly tall (1.5-3 m or more) perennial grass of wetlands, with large purplish panicles that form erect or slightly nodding plumes, deep purple when young, becoming straw-coloured as the grains mature and the silky white hairs that aid seed dispersal become prominent. The plants often form large patches by means of both rhizomes (underground stems) and stolons (above ground, horizontal stems). The leaves occur all along the stem and have blades over 1 cm wide. The leaf sheaths do not completely cover the stems but expose the upper segments of stem between two leaf sheath junctions (internodes) which are smooth and conspicuously reddish. The panicles are 10-40 cm long with filiform ascending branches bearing the stalked spikelets. These are large at 1.5 cm long, with long, silky white hairs attached to their axes; their three to several, narrow florets bear similar hairs towards the base. The lower glume is one-veined and about 4.8 mm long, the upper three-veined and longer at about 5.5 mm; the lower lemmas are about 1.5 cm long (as long as the spikelet and hairs), narrow, folded, and drawn out to a narrow point, and a darker brown than the glumes. The large purplish anthers are 1.8-2 mm long
Because European weed is common in the Maritimes, Quebec and Ontario, and is a threat to native biodiversity (both plants and animals), much research has been undertaken since the 1990s to distinguish it from the native subspecies and to track its spread. It is expected to become abundant in the western provinces in the future and could become an agricultural menace in Alberta’s irrigation districts. American reed can be distinguished by its red or red-purple lower stems, which are green in European reed, and by its longer glumes (over 4.4 mm long versus 2.8-4.4 mm in European reed), although there is some overlap. Although European reed has likely been in North America since the late 1700s, introduced accidentally with ship’s ballast, its rapid spread in Canada during the 20th century is attributed to road development, with rhizome fragments being transported by ditching equipment. Waterfowl also spread rhizome fragments and seed dispersal is effected by wind. Non-native Phragmites can grow in a variety of wetland soils of differing pH and it modifies the local environment to suit itself. Interestingly, it is not nearly as invasive in its native lands in Europe, possibly in part because it is often grazed by cattle there. Ironically, spread may also be facilitated by the “no net loss” wetland policy in North America, whereby wetlands that have been lost to development have to be replaced by new wetlands elsewhere. These anthropogenic wetlands are particularly vulnerable to invasion by the weedy European reed. Various methods of control are being explored in both the US and
Canada.
The situation is similar to that of reed canarygrass in which native and non-native varieties occur, except that in the case of this species the latter is by far the more prevalent in Alberta. I have found American reed on shores at Moose Lake Provincial Park, of lakes in Cooking Lake-Blackfoot Reserve, South Cooking Lake (which is particularly saline), and Clifford E. Lee Nature Sanctuary, and I am reasonably confident that all populations were native.
Foxtail barley, squirreltail barley, Hordeum jubatum
Foxtail barley is a native, tufted, perennial grass with stems that are erect or bent to one side, reaching 30-100 cm tall. It has flat leaf blades and an inflorescence consisting of a nodding, dense spike that appears bristly due to the long awns on all the flower parts. The heads are an attractive green or pale purple, becoming straw-coloured at maturity when they start to break up. There are three spikelets at each node of the spike, the two lateral ones on short stalks and consisting only of 1-3 awns. The central, fertile spikelet lacks a stalk and contains a single floret. The glumes of this floret are narrow and rigid and vary from short (ca. 3.5 cm) to 9 cm long, and extend into long awns; the lemma is 5-7 mm long with an awn as long as the glumes. The elliptical grains also bear long (ca. 7 cm) awns.
This grass is common and familiar on open waste ground and roadsides in urban situations, especially where roads have been salt-treated. However, since it favours soils with a high pH (alkaline) it is particularly abundant around saline lakes, colonizing shorelines aggressively as the water line recedes. Easily recognized, foxtail barley is an ornamental grass to some and a weed to others. Ranchers, for example, particularly dislike it as the awns, equipped with minute barbs, are injurious to cattle’s mouths.
Two subspecies are distinguished. Subspecies xintermedium occurs from BC to Ontario and has shorter glumes and lemma awns than the typical subspecies, subsp. jubatum, which is widespread across Canada (introduced in Labrador) and the U.S. (except the southeast). Foxtail barley has an interesting pedigree: it is a hybrid of polyploid origin, from natural crossing of a Siberian Hordeum species with an extinct relative of the meadow foxtail, Hordeum brachyantherum, that grows in California. If you come across a grass that looks a bit different, rather like skinny-spiked foxtail barley or a long-awned wheatgrass, you may have encountered the hybrid, Macoun’s wildrye, xElyhordeum macounii, a cross between slender wildrye, Elymus trachycaulus, and Hordeum jubatum.
References
Canadensys Vascan (online)
Catling, Paul M. & Gisele Mitrow. Major invasive alien plants of natural habitats in Canada. 1. European Common Reed (often just called Phragmites). 2009? CBA/ABC Bulletin 44 (2), pp. 52-61.
Flora of North America, Hordeum jubatum, Vol. 24, p. 245.
Flora of North America, Puccinellia nuttalliana, Vol 24, p. 475.
Flora of North America, Puccinellia distans, Vol. 24, p. 473.
Kershaw, Linda and Lorna Allen. 2020. Vascular Flora of Alberta. An Illustrated Guide. Self-published. Kindle Direct Publishing.
Moss, E. H. 1983. Flora of Alberta. 2d ed. edited by J.G. Packer. Toronto, University of Toronto Press.
