Plains Rough Fescue – Festuca hallii (Vasey) Piper

Tribe Poeae

Synonyms or Other Names:

Festuca hallii is commonly known by local ranchers as “Prairie Wool.” Historically named Festuca altaica ssp. hallii (Vasey) Harms.

Origin & Status

Uncommon. Native to North America. Estimates that small, isolated pockets of this species remain scattered in still-intact prairie habitats.

Notable Features to Identify:

Festuca hallii is a bunchgrass that grows 20 to 65 cm (8 to 26 inches) tall and has short rhizomes.

The leaf blades are narrow, 1 to 1.5 mm wide, about 30 cm long, and long-pointed. They are in-rolled but folded at emergence. Blades are also rough above and smooth below and bluish or grey-green.

Sheaths are round, hairless, shiny and ridged, occasionally with a purplish tinge and purple at the base. Old sheaths often remain persistent and are split. Sheath margins overlap and are pale in colour. Ligules appear lacerated and hair-fringed and are typically short and not prominently notched. Collars are not distinct and yellowish, and there are no auricles present.

The heads are in the form of panicles that range from 6 to 15 cm long. They can be open or contracted. The spikelets are 2- to 3-flowered, with the third floret sterile, and glumes nearly equal (6 to 7 and 7 to 8 mm long) and as long as the first lemma (lemmas 7 to 8 mm long). These glumes are hairless, somewhat shiny, often suffused with purple, and the lemmas are more roughened with tiny hairs and purplish. There are no awns present.

Where & When to Find This Plant:

F. hallii is found primarily in the Parkland Ecoregion. It is a dominant climax species commonly found with Blue Grama (Bouteloua gracilis). It may be challenging to find this plant in areas except where it has been largely untouched by cattle grazing and agricultural activities, such as in provincial parks such as Big Knife or Dry Island Buffalo Jump.

Its range is from the mixed grasslands and northern edge of the Great Plains eastward to Ontario, with some populations in the southern interior of British Columbia. It is also found in through Montana south to New Mexico according to the USDA Fire Service database.

F. hallii typically blooms during the summer months, from June to August (as I’ve observed here in Alberta). However, some years have seen climate conditions that discourage this species from sending up inflorescences, and they will remain predominantly vegetative instead.

Is this Species Edible, Medicinal, or Toxic?

This species is highly palatable to livestock and wildlife. No other information is recorded as far as its value to people for edible, medicinal, or toxic effects.

What Other Species Can This Be Confused With?

F. hallii can be easily confused with Festuca campestris (Foothills Rough Fescue) and Festuca altaica (Altai Rough Fescue). F. campestris resides primarily in the foothills, whereas F. hallii is mainly a prairie grass. Festuca altaica is a northern species that prefers cooler climates and higher elevations.

F. hallii is distinguished from the other two species by having only 2 to 3 florets per spikelet. F. campestris and F. altaica, by comparison, have 4 to 6 and 3 to 5 florets per spikelet, respectively. Altai Rough Fescue has yellowish to dark green leaves, whereas Foothills and Plains have grey-green to bluish-grey leaves.

Plains Rough Fescue tends to be shorter in stature than either of the two. Foothills can get up to 90 cm (36 inches) tall, and the shortest recorded plant of F. altaica is 40 cm (16 inches).

F. campestris and F. altaica form larger bunches with more culms per bunch than F. hallii.

Other Interesting Information:

F. hallii is a valuable rangeland species for both wildlife and livestock because of its high palatability and ability to retain its nutritional value in the winter months. However, poor grazing management and agricultural activities threaten its existence. Some have estimated that less than two to five percent of intact F. hallii rangelands remain; these are small, isolated pockets in well-managed private or federally/provincially protected lands.

Other challenges include its high dependence on seed production for its ability to spread, its slow establishment and reproduction ability. Seed production can also be quite variable, as in some years, F. hallii may produce very little to no seed, and in other years, conditions will be perfect for seed production, such as that pictured above.

Festuca hallii also stands as the provincial grass of Alberta.

Ranchers call it prairie wool because of the many clumps of dead, brownish-grey plants that look similar to sheep’s wool.

Value to Livestock & Wildlife

All rough fescue species provide high-quality pasture or range fodder for livestock and wildlife, especially for winter grazing. Animals seek out these plants all year round to eat. As with all plants, young, fresh green leaves and stalks are the tastiest, with both the quality and “taste factor” (or palatability) declining as plants reach maturity. Rough fescue maintains its quality into winter, capable of curing on the stem as it matures. This makes it a highly sought-after food source for grazing animals in the winter.

However, old residue from previous years can reduce palatability. Studies have shown that elk favour winter grazing rough fescue if the old residue is cleared out by fire and grazing (primarily by cattle). Studies also have shown that heavy grazing, overgrazing, and grazing in early fall will cause rough fescue stands to decrease and other “increaser” species to creep in and replace it, such as Parry’s Oat Grass (Danthonia parryi), Idaho fescue (Festuca idahoensis) and wheatgrasses (Family Triticeae), especially here in Alberta. Rough fescue is especially sensitive to summer grazing. It thrives much more under winter grazing.

The migration patterns of the Great Plains bison (Bison bison bison) have traced them to spend their summers in the southern Great Plains (mainly in the midwest and east of the Rockies of the United States) and then move north to Canada for their winter range. They are thought to have only gone as far north as the Aspen Parkland ecoregion and the prairie fescue grasslands and west to the foothills east of the Canadian Rockies. For this reason, it is believed that rough fescue evolved with the winter grazing habits of the old enormous bison herds.

With bison grazing considered “moderate” by scientists and biologists, they would have utilized those plants as their primary nutrition source in the winter, along with sedges and other grasses. When it was time to migrate back south for their summer grazing (a few scattered groups of bison remained behind, similar to the animals of the Serengeti in the African continent), these rough fescue plants were left behind and allowed to recover, grow, and reach maturity before the bison returned.

Suitability/Use for Reclamation

It is a common plant to use in a reclamation mix to establish disturbed sites in prairie grassland. However, its use is challenging due to high seed prices, short supply, and the long establishment period. Once this species successfully establishes itself, though, the persistence of this beautiful grass is quite admirable.

Gallery

Coming soon!