The Nature Conservancy Utah has gained ground on thousands of acres of wetland in its yearslong battle against the invasive grass using its own herd and cows from local ranchers.
Syracuse • Conservationists, waging a yearslong battle against an invasive marsh reed grass that has choked out native plants and wildlife in the wetlands near the Great Salt Lake, have enlisted an unlikely ally: Cows.
The animals are part of a tactic The Nature Conservancy Utah employs to fight back against phragmites, water-sucking non-native stalks that have taken root in the Utah wetlands over several decades.
For the last three years, the group has been using cows — along with herbicides and an amphibious machine — to fight back against phragmites (pronounced “frag-MY-teez”). This year, the group added another tool to its arsenal by putting GPS collars on some cows.
The invasive plant is likely around to stay, said Chris Brown, stewardship director for The Nature Conservancy Utah.
“Are we ever going to get rid of it?” he said. “Probably not.”
The battle, he said, has proven conservationists can make it manageable and less harmful to the Great Salt Lake.
As massive areas of the Great Salt Lake’s lakebed remain dry, it’s important to fight the phragmites so water can flow through wetlands to the lake. The plants can suck up large amounts of water and grow to 10 feet tall, blocking wildlife from reaching the water, Brown said..
Invasive grass arrived in the 1980s after flooding
Conservationists have fought phragmites for years in the eastern United States, notably around the Great Lakes, Brown said. But the tall, thirsty plant, native to Europe and Asia, didn’t invade the Great Salt Lake wetlands until around the 1980s.
Phragmites, with a tenacious root system and thousands of seeds, took hold and thrived when the lake began to recede after massive flooding and left a scar of nutrient-rich runoff in the wetlands, Brown said.
In the decades since, phragmites has depleted vast amounst of water.
Researchers with the Utah Division of Water calculated the reedy grass sucks 71,000 acre-feet from the Great Salt Lake each season. That’s the equivalent of all the water flowing from the Jordan River for nine months.
Phragmites also has choked out important bird habitat in the wetlands, including thousands of acres at the Great Salt Lake Shorelands Preserve.
(Bethany Baker | The Salt Lake Tribune) Phragmites, an invasive species, and other native species are seen growing together during a media tour at the Great Salt Lake Shorelands Preserve in Syracuse on July 16, 2024.
Like other wetland managers around the Great Salt Lake, the conservancy uses a combination of herbicide spraying, rolling and crushing to control phragmites.
An old management strategy — burning the grass — led to air-quality issues, Brown said, and isn’t used any more.
The Nature Conservancy primarily uses herbicide sprayed from aircraft and an amphibious vehicle called the Marsh Master to knock phragmites to the ground during winter.
In the summer, though, cows take center stage.
For cows, phragmites are a protein-rich snack
Cows had always done some grazing on the Great Salt Lake Shorelands Preserve, Brown said.
Then within the last few years, he said, the organization noticed the herds saw the invasive grass as a tasty snack.
“We found that the cows kind of like the phrag,” he said.
Phragmites is rich in protein, Brown said, but the reedy grass doesn’t have any benefit for birds and other species that call the wetlands home.
Cattle grazing is an ideal solution, he said. It’s “free labor” and keeps the phragmites from producing seeds, he said, allowing native plants to start taking over and fighting back.
In the area where about 300 cattle were grazing on 200 acres Tuesday morning, there had previously been a 10-foot-tall field of phragmites, Brown said. Cattle grazing reduced the stand by 30% on a 4,000-acre area that was largely covered with the invasive grass, he said.
Native cattails and bulrushes dotted an area beyond the herd, and a pair of sandhill cranes called loudly as they flew amid the grasses.
The Nature Conservancy has done bird surveys after cattle grazing and found “almost a tenfold increase” in the population of waterfowl and shorebirds, Brown said.
Cows don’t like to eat the native plants, he said. As they move on to find more of their preferred reedy snack, he said, they also then trample and break up dead plant material.
Other wetlands, including Ogden Bay Waterfowl Management Area, have used cows as a tool to fight back phragmites.
The strategy benefits the wetlands and the farmers, Brown said. The Nature Conservancy has its own herd of about 70 cows, he said, and the remainder come from local ranchers who are “running out of places to take cows” to graze, he said.
Cows will wander, GPS collars are a possible solution
Though the strategy has benefits, letting cows loose on the phragmites did present a small problem.
“Cows tend to be cows, and they want to wander around,” Brown said.
That means installing fencing, he said, but it can be hard to install a physical fence in many areas of a wetland.
The Nature Conservancy is working on a solution to that, with a new project in partnership with Utah State University that uses a sort of shock collar tied to a GPS unit.
The collars allow Brown to “draw lines around areas where there are phragmites” and then contain the cows to those areas without a physical barrier.
The nonprofit has collars on about 200 cattle at the south end of the shorelands preserve right now, Brown said.
