Species Profile

Mackenzie Hairgrass

Scientific Name: Deschampsia mackenzieana
Taxonomy Group: Vascular Plants
Range: Northwest Territories, Saskatchewan
Last COSEWIC Assessment: November 2001
Last COSEWIC Designation: Special Concern
SARA Status: Schedule 1, Special Concern


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Quick Links: | Photo | Description | Distribution and Population | Habitat | Biology | Threats | Protection | National Recovery Program | Documents

Image of Mackenzie Hairgrass

Mackenzie Hairgrass Photo 1

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Description

This perennial grass species has densely tufted stems which grow from fibrous roots. The leaves are mostly basal, with narrow, involute or folded blades. The ligules are large, 3-5 mm long. The panicles are large, open, light straw-coloured, 10-20 cm long. The spikelets are 6-12 mm long, with 2 or 3 flowers. The glumes are narrowly lanceolate and 5-10 mm long, and the lemmas are glabrous, 4-6 mm long, with callus hairs 2-3 mm long. The anthers are over 2 mm long and the caryopses are about 2 mm long.

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Distribution and Population

The species is endemic to Canada, with its total range restricted to the sand dunes on the south shore of Lake Athabasca in northwestern Saskatchewan. It is relatively frequent locally, occuring as scattered large tufts or in small groups of 3-5 or more plants. The overall cover of the plants over the larger dune fields is estimated at about 0.1%. A very rough population estimate is >300,000 plants. There is no indication that the population is declining.

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Habitat

The plants occur in large, open, active sand-dunes, where they are found mostly on leeward slopes, just over dune-crests, and at bases, depressions and slacks between rolling dunes. They seem rare or absent on smaller parabolic dunes, and seem excluded from more stabilized or even semi-stabilized sand-dune sites. Mature plants appear able to tolerate a considerable deposition of dry sand, since their diffuse root systems extend down to the moist and more nutrient-rich layers below.

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Biology

The Mackenzie Hairgrass appears to consist of bisexual, self-incompatible, sexually outcrossing plants. Seeds apparently require a winter cold-treatment prior to their germination in spring. A long-day photoperiod seems needed for flowering induction. In the Lake Athabasca dune region, expanded panicles were noted by early to mid-July, and mature caryopses by late July to September. Numerous seeds and seedling plants have been observed in nature, and seed variability appears high. Seedling survival seems to be determined by the vagaries of the shifting sands. The species has been shown to have low genetic variability, presumably due to lack of dispersion.

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Threats

Due to its low genetic variability, the species would probably adapt less readily to habitat change. It appears to be quite restricted to its specific active sand-dune habitat, and the relative lack of competition from other plants within this region. Therefore, any alteration of its habitat could represent a limiting factor for the species. Potential threats to the habitat include damage by all-terrain recreational vehicles, over-trampling by tourists, or any development in the area (e.g., mining, cottage-building) that would increase public access and the introduction of exotic weeds.

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Protection

Federal Protection

More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.

A population of the Mackenzie Hairgrass is found within Athabasca Sand Dunes Provincial Wilderness Park.

Provincial and Territorial Protection

To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.

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Documents

PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.

1 record(s) found.

Management Plans

  • Management Plan for Multiple Species of the Athabasca Sand Dunes in Canada (2013)

    This management plan addresses a group of seven plants which are listed as species of special concern under the Species at Risk Act (SARA), and which are found in the Athabasca Sand Dunes of northern Saskatchewan: Large-headed Woolly Yarrow, Athabasca Thrift, Mackenzie Hairgrass, Sand-dune Short-capsuled Willow, Felt-leaf Willow, Turnor’s Willow, and Floccose Tansy. The Athabasca Sand Dunes is a complex of active and stabilized dunes on the south shore of Lake Athabasca, in the 1925 km² Athabasca Sand Dunes Provincial Park which is located in the northwest corner of Saskatchewan. These plants are endemic (i.e. found nowhere else) to the dune complex, with the exception of one reported location of Felt-leaf Willow in Nunavut, one reported location of Mackenzie Hairgrass in the Northwest Territories (both under review), and a few observations near to the dunes on the shores of Lake Athabasca.