SASKATOON —麻豆传媒AVwest of Calgary, as the jagged peaks of the Rockies level out to the Prairies, rough fescue grows in dense tufts. This native plant is Alberta’s provincial grass and a tasty meal for livestock in the fall and winter.
Saskatchewan’s provincial grass is needle-and-thread grass, named after its sharp seed tip and long awn. Anyone walking through a pasture of this native grass will later find seeds stuck to their socks.
These types of native species used to be common on the Great Plains, feeding herds of wild animals. Now, they are rare and becoming rarer still.
They also tell a story, experts say, about the history of land disturbances, as well as soil quality. And if producers can decode those stories, the plants can help them decide how to manage their pastures.
At the Saskatchewan Forage Council’s 2023 Pasture Tour near Cochin, Sask., Jeremy Brown kneeled in a pasture, showing people how to identify native plants and what those plants reveal about the land.
At the time, Brown worked as an agrologist for Ducks Unlimited Canada. He now splits his time between his mixed operation and his work as an ecologist consulting on rangeland and water.
He says long-term effects can be deduced by the number of native species on a person’s land.
“There are indicator plants that can give you indicators about the historic use or disturbance of the pasture or site,” Brown says in an interview. “If the plant community evolves over time, individual species become more or less dominant in response to the growing conditions and also disturbances like fire, grazing or mechanical disturbances.”
Professional agrologist Stephanie Jaffray is an expert when it comes to native plants. She sees them as indicators of soil quality.
“I think when you have a good growth of native plants in your field, which means the majority of plants growing there are native, I think what you realize is that you are going to have healthy soil. You’re going to have really good biodiversity,” says Jaffray, who lives in Lethbridge.
She echoes Brown’s point about native plants indicating disturbance history of the land. It’s hard to re-establish some of them after a disturbance, she says.
“Once native plants have been taken from an area and disturbed, I liken it to scar tissue. If you’ve got some bare ground, you’re going to have to have something growing there. But a lot of weed species and agronomic types of species, they’re opportunists. They’ll come in and they’ll take over.”
Brown and Jaffray had a few suggestions for specific species to watch.
Brown says if the soil isn’t good, producers will see a reduction in favoured plants, such as rough fescue, needle grasses and wheat grasses.
“And initially you’re going to see increases in short grasses like blue grama and june grass and sedges.”
Following that, he says producers might see an increase in plants such as yarrow, pussytoes, pasture sage and wild strawberries that indicate the plant community has been affected.
He says there is a misconception that pasture sage is aggressive and chokes out other plants. In reality, it doesn’t affect pasture production and may suggest a producer should work to improve forage health.
Jaffray mentioned rough fescue as an important native plant in Alberta, as well.
“If you go out into your field and you’ve got rough fescue growing out there, you know you’ve got a good thing going.”
She says a good amount of rough fescue in a pasture is 50 to 75 per cent. That much rough fescue, as well as species such as forbs and other native grasses, assures producers their land is healthy and they are not overgrazing or stressing the area.
Jaffray says in eastern areas of Alberta, producers should keep an eye out for wheatgrasses, which indicate they are doing something right on their land. In the southeast, it’s native needle grasses.
She says having several different plants on pasture indicates good soil health.
“You don’t want a field that’s just 100 per cent rough fescue. You need that biodiversity to keep your lands healthy.”
Once rough fescue dies out, it’s almost impossible to re-establish, even if the producer creates favourable conditions. This is why rough fescue is considered under threat.
“It doesn’t regenerate. It doesn’t grow quite as easily as other grasses,” Jaffray says.
Researchers are studying different ways to re-establish rough rescue, by planting plugs are seeding, but without much success.
“If you have some of those rough fescue plants, let them reseed themselves over a few years and that reseeding is what will actually help bring that grassland back,” Jaffray says. “That goes for any type of grasslands. You don’t want to have to put a lot of money into reseeding native plants — it’s very expensive. So, if you have the ability to give those pastures some rest, I think that’s really, really important and will help a lot.”
As a rancher, Brown thinks it’s important for producers to know the soil type and disturbance history on their land. By understanding the native species they are fostering, Brown says producers can make informed management decisions.
“On native range, the plant species will greatly determine your forage productivity. So I think it’s important to be able to identify some key decreaser species and some key increaser species, so that you can observe what your current state is, but also how that’s changing over time.”
Producers pleased with the results might carry on with their current management approaches, he says. “Or if you’re not pleased with the results, then you can look to how you can adapt your grazing management to achieve your goals.”
Jaffray says a producer can tell the state of their land by the plants growing there and then can make changes based on that.
“If you have a really good mix of native plants, forbs and grasses and shrubs, I think you’re doing really well,” she says. A piece of land with over 50 per cent Kentucky bluegrass, smooth brome, timothy or crested wheatgrass means “you’ve got some issues.”Native prairie once covered Western Canada. Before settlers, these plants grew along with and nourished herds of bison, elk and other wildlife native to Canada.
Now, they are a rare commodity, and that causes concern within the agricultural industry. Less than one per cent of native grassland in Saskatchewan and Alberta is protected.
Jaffray says with recent data suggesting native grasslands sequester large amounts of carbon, more effort should be put into maintaining and nurturing native plants.
“Once you break that native grass and once you break that soil, you’ve broken it and it’s going to be very, very difficult to get it back. And you’re going to be releasing all of that carbon dioxide in the atmosphere.”
She says native species are also critical for keeping the ground covered in vegetation.
Brown says failure to nurture these types of plants can cause issues in the plant community on a producer’s land and can take decades to recover.
“And so you want to make sure that you’re not affecting your plant community in a negative trend or for any extended period because the reversing of that happens very slowly.”
