Defend The Core: Fighting back against rangeland invaders in sagebrush country

Healthy Sagebrush Benefits Everyone

Working Lands for Wildlife is investing in proactive ways to keep sagebrush lands free from unwanted weeds like cheatgrass. Invasive annual grasses spread fast, outcompete desirable forage for livestock , and fuel more frequent wildfires. They are bad for agricultural business, bad for wildlife, and bad for rural communities.

The best way to prevent the spread of invasive annual grasses is to defend America’s intact rangelands. Keeping these core areas free from invasive grasses will ensure our grazing lands remain productive and profitable long into the future.

What Are Core Areas?

Envision driving through a western ranch with the windows down. Tall green and gold bunchgrasses wave in the wind. Wildflowers bloom between waist-high shrubs. The sunny afternoon is alive with birdsong and buzzing insects, the air clean and scented with sage. This is what we call the intact core: large areas of healthy, thriving native rangeland.

But as you drive farther towards the horizon, you start to notice less green and fewer flowers. The ground turns shades of brown, tan, and purple. The graceful bunchgrasses are now interspersed with short, dry grasses, their seeds pricking through your socks.

This transition zone is where healthy range is giving way to invading weeds like cheatgrass, ventenata, and medusahead.

Drive even further from the core, and unpleasant invasive annual grasses have choked out most native plants. Wildlife is few and far between. Rangelands this infested are much less productive for ranchers and wildlife. Plus, they are extremely difficult and costly to restore.

Luckily, people who depend on and care about America’s valuable sagebrush lands are banding together to fight back against unwanted invaders.

Through Working Lands for Wildlife, the USDA’s Natural Resources Conservation Service is investing in a new, proactive strategy: First, defend the core. Second, grow the core. Third, mitigate impacts in heavily infested areas.

Flipping The Script

If it sounds like battle tactics, that’s because western landowners are indeed engaged in a war on weeds, and have been for over a century. A shift in strategy is overdue. The status quo—reactive, piecemeal treatments once invasive annual grasses become a problem—hasn’t worked.

“In the past, we would go to the worst places first, which is like sending in an ambulance when the land is already in need of life-support,” said Jeremy Maestas, a USDA-NRCS ecologist.

Instead, WLFW is “flipping the script,” explains Maestas, to prioritize preventative care for healthy, intact places in order to keep them productive and expand them. “I think of it as providing annual checkups to keep the land thriving, instead of a last-ditch visit to the ER when it’s already a crisis.”

Until recently, conservation practitioners lacked the technology to see where the remaining intact rangelands remain. No one could see exactly where invading grasses were coming from, or how fast they were infiltrating core areas.

Breakthroughs in remote sensing have enabled scientists to now see the big picture and how lands have changed over time. Detailed vegetation maps, along with easy-to-use tools like the Rangeland Analysis Platform, are finally giving landowners and resource managers the information they need to fight weeds on a regional scale, rather than trying to save tiny islands.

WLFW is partnering with local, state, and federal managers to prioritize where and how to halt rangeland invaders by mapping intact cores and see where invasives are taking hold. These maps form the basis for developing a shared game plan for directing conservation investments.

Defend The Core, Grow The Core

Land managers have long known that it’s far more cost-effective and efficient to treat weeds early before they spread. The trick, however, is working in the right landscapes and simultaneously treating infestations on adjacent rangelands so invasive annual grasses don’t quickly re-invade.

“These problems are contagious,” Maestas said. “You can spray cheatgrass in your backyard until the cows come home, but if all the neighboring lands around you are infested it’s an exercise in futility.”

Put more succinctly: “If there’s no seed, there’s no weed.”

In sagebrush country, the best way to keep out invading annual grasses is to prevent them from ever becoming established and to maintain a resilient, healthy native plant community that allows no room for incoming weeds.

“Job number one is to defend the cores,” Maestas said. “If we anchor our efforts here then move our way out, we’re less likely to get flanked by invasives.”

Defending cores means continually monitoring for any invasive annual grasses, and caring for native range plants.

The next priority is to grow these cores by bolstering perennial plants and removing invasive seed sources on their periphery. In sagebrush landscapes, this often includes using herbicides on invaders, followed by re-planting native grasses, shrubs, and forbs.

The third priority is to mitigate problems in heavily infested areas to minimize harm to human life and property. Mitigation measures might include building fuel breaks to protect homes, build green strips around pastures, or targeting livestock grazing in the spring to reduce the build-up of fine fuels (grasses) before they can spread wildfires.

Hope In Action

WLFW’s “Defend the Core” approach is already being deployed in several western states. Idaho’s Cheatgrass Challenge and Oregon’s SageCon Invasives Initiative are both pioneering a statewide strategy for tacking invading weeds. The University of Wyoming’s Institute for Managing Annual Grasses Invading Natural Ecosystems (IMAGINE) is hosting workshops and webinars to teach people how, when and where to apply herbicides.

WLFW is poised to help more states develop big-picture strategies to “Defend the Core”, guided by our Framework for Conservation Action in the Sagebrush Biome. In addition, WLFW is investing Farm Bill conservation dollars on hundreds of ranches each year to fight back against invasive annual grasses and maintain healthy working sagebrush lands.

“This is a new, proactive path forward: save what’s intact and build out from there. It requires neighbors working together to pinpoint and protect the best rangelands left,” Maestas said. “This is how we get ahead of invasives instead of simply chasing the worst problems.”