Grazing response index | The index was designed for native pasture in the U.S., but Canadian researchers take it for a spin
Officials are confident that an American pasture health assessment tool can assist prairie ranchers in Canada.
However, the grazing response index created by Colorado State University researchers has never been tested in tame pastures, such as those commonly found in eastern Saskatchewan.
“In the parkland (region) we don’t have a lot of native pasture left,” said Jodie Horvath of Ducks Unlimited.
“I think the average producer in this area would be using a tame pasture. It does act a little bit differently.”
Horvath is overseeing three sites at Ducks Unlimited’s Touchwood Hills Conservation Ranch to test the grazing response index.
The project is funded through Sask-atchewan’s Agriculture Demonstration of Practices and Technologies initiative.
The system uses observations made in the field to help producers assess the impacts of grazing and make management decisions.
Producers use guidelines to make observations about the frequency and intensity of plant defoliation, as well as the opportunity for regrowth, assigning a number to each category on a scale of minus two to plus two. At the end of the year, the producer will have a positive, neutral or negative number.
“We wanted to capture the time commitment that it would take to do these sorts of things because that’s one of the things of course that comes into play for everybody on their operation,” said Leanne Thompson, executive director of the Saskatchewan Forage Council, which is also involved with the project.
A positive number shows beneficial management, while a negative number indicates the area has been over-grazed. From there, producers may modify how they use the paddock: extend recovery time, change stocking rates or graze the area for a shorter period of time.
“I think what it does is it … allows you for more quick decisions, I guess, having a quicker impact maybe on the pasture rather than looking at the overall tame (pasture) health and long-term viability of the stand,” said Horvath.
It’s not meant to replace long-term monitoring, she said.
As part of the project, Horvath will also conduct a traditional tame pasture health assessment.
Thompson said the data recorded as part of the GRI system would be familiar to anyone who does rotational grazing.
The system relies on observations made in the field and basic record keeping — when animals were moved and how long they stayed on pasture —rather than measurements of specific plant species, which makes it less intensive than rangeland or tame pasture health assessments.
“There’s a more intensive amount of information gathered in those assessments. This one is really meant to be a little more producer friendly, something you could do every year, and that’s how it’s supposed to be used,” she said.
“Whereas maybe your rangeland health assessment, you might only do that once every few years.”
The grazing response index has already been tested and used in Canada but not on tame pastures, where plants such as meadow brome recover more quickly than native grasses and are grazed more intensively.
“I think we’re pretty comfortable with the fact that we can use it. We just want to showcase what we did (and) how we applied it using the area that we are in at the ranch,” said Horvath.
“It’s a valuable asset to have there because it’s a working ranch.”