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Success Story

Ventenata Control: One Problem, Two Solutions

Ventenata, also know as North African Wiregrass, is a rangeland invasive species. Big Horn County, MT

Hear from three producers across Big Horn County and the Crow Reservation that are using different methods to control the invasive warm season grass, ventenata.

Ryan Rigler, Clay Gregory, and Mickey Steward are all working to improve the condition of their grazing lands by mitigating the impacts of invasive species.

Read about their work in the Ventenata Control: One Problem, Two Solutions Story Map. Find a text-only version of this story below.

Watch their story in Conservation for the Future: Ventenata Control, Big Horn County, MT.

Ranch of Clay Gregory, Crow Indian Reservation, MT.

Big Horn County, the sixth largest in the state, sits along the south-central border of Montana. Much of the county’s land area lies within the Crow Indian Reservation with agriculture playing a significant role in the area’s economy. “We are largely livestock production in this county, mostly rangeland for land use,” explains NRCS Tribal Conservationist Evan VanOrder. “It is the economic backbone for many families in this county. As we know, cows eat grass, the more grass we have the more resilient our rangeland is and the more resilient the whole operation becomes.”

When forage production is threatened across native rangelands, there is cause for concern. Such was the case when the winter, annual invasive grass Ventenata began to make an appearance throughout the county. “I had no idea what it was but noticed nothing would eat it,” states rancher Ryan Rigler who operates west of Lodge Grass. Crow Tribal Member and producer Clay Gregory concurs, “The green on Ventenata is maybe only a two-week period so you don’t get any nutritional value out of it. Cattle will graze it in the spring when it’s green, but it’s not their go-to plant. I don’t think they really prefer it.”

Over the next few years, Ventenata became more than an unappetizing nuisance; it began to take over rangelands and choke out native species. “We’ve actually seen rangeland that was almost 90% covered with Ventenata,” states NRCS Supervisory District Conservationist Seanna Torske. “It can take a while to break down due to its high silica content, it’s a huge wildfire hazard, and it also makes it difficult for other native plants to take root. NRCS’s VanOrder agrees, “There’s a reason those winter annual invasives are showing up. Usually, this is because the ground is providing an opportunity for those plants to get established.”

Local working groups recognized the increasing weed problem across the county and identified it as a top resource concern. “Montana Focused Conservation focuses on conservation practices in a targeted geographic area and addresses specific resource concerns using a specific suite of practices,” states NRCS’s Torske. “NRCS set up a Targeted Implementation Plan (TIP) to address weed species in our county, primarily Ventenata or African Wiregrass.”

The Ventenata Control TIP offers a variety of approaches for producers including cross fencing and prescribed rotational grazing or chemical application followed by grazing deferment and range management. To tackle Ventenata, NRCS worked with individual producers to customize plans that worked best within their operational goals and objectives.

Producers Rigler and Gregory are two program participants who opted for chemical treatment followed by grazing deferment. “We took the opportunity to take advantage of the program to help see if we could control this Ventenata better,” states Gregory. “We don’t have the luxury of a lot of acreage for grazing, so for us, we try to take care of the land the best we can.” Because of the rugged terrain, Gregory chose helicopter application on an initial 283 acres, followed by a year of deferment. Rigler, one of the first to participate in the program, started with a smaller 40-acre plot for the first year’s chemical application, adding more acreage over subsequent years. “With electric fences we have it broken up into manageable parcels and we’ll try to spray each one of those parcels a year,” states Rigler.

After treatment and during deferent, improvements to the land and the return of native species was evident. “The rhizomatous native grasses really showed an improvement,” states NRCS’s VanOrder. “Other natives did well after that first treatment and after the deferment, it allowed those native grasses to really get established and start to flourish again.”

As for the elimination of Ventenata, “I would say we have in excess of 95% control on these first sprayings,” states Gregory. “Treating it was successful and we are incorporating it into our management plan. I never would have tried it without the help of NRCS, I don’t think. Once you see the results and what it does, I think it’s a good thing and it’s cost effective,” agrees Rigler.

Another participant in the TIP program, Producer Mickey Steward of Seacross Ranch, opted to forego chemicals and work within her already established rotational grazing program. “My experience with grazing and what livestock can do to the landscape made me think that perhaps we could use a grazing program that would, if not eliminate the Ventenata, allow us to control it to levels where it was a part of the landscape - but not a dominate aspect that was affecting our ability to produce,” she explains.

With the help of NRCS, Steward developed a monitored, rotational grazing strategy to improve the landscape’s cover, diversity and production of native vegetation. “We generally work with about forty paddocks per year, keeping them smaller in the spring. We really rip through them in the spring and as the summer advances the paddocks get larger,” Steward explains.

During the season in which they can expect the best recovery, the Stewards use electric fencing to set up paddocks from thirty to one hundred acres. “We use that to non-selectively graze. When the cows go into a new pasture, it’s clean and fresh and nobody’s nibbled on it so they go out and basically eat everything.”

NRCS District Conservationist Nikki Rife agrees, “The key to any successful grazing is controlling the duration and recovery. We can’t control what they graze unless we’re controlling the size of the space that the animals are in or through their behavior. And the only way to change that is through the size of the pastures and water distribution.”

“Vegetation’s opportunity for recovery is not as great as it is earlier in the year; that leads to the most critical point of forage management,” states Steward. “That is, you must stimulate the forage, grasses and forbs that you want to encourage, and you must give the landscape a chance to recover. What we are really trying to do is give the desirable species a competitive advantage that allows them to persist and expand in the face of the Ventenata.”

Using transects, photo monitoring, and observation of sensitive sites and high density Ventenata areas, the Stewards have started to see an increase in native grasses and less dominance of Ventenata. “We can see, despite having been reasonably dry this year, this pasture is in good condition. This is not a quick fix. But it will be very exciting over the next three or four years to see if we are succeeding in directional and positive change,” states Steward.

“It’s exciting to work with producers that are excited to change their landscape and do it with grazing. I am happy to do all I can to help them,” concludes NRCS’s Rife.

Despite different approaches, all three producers share a dedication to being good stewards of the land both now and for the future. Steward says it best, “What you manage for is what you want, not what you don’t want. It’s not to destroy the things you hate but to protect the things that you love. The way to manage a landscape is to nurture the things that you love. We are on a mission to make it better and that’s what makes our life meaningful to us.”