Unhealthy competition

Invasive species are a leading risk to native wildlife everywhere, including the greater sage-grouse and hundreds of other species that depend on healthy sagebrush habitat. Invasive plants compete with sagebrush and native grasses and flowering plants for water and nutrients in the soil, and for living space above and below ground. 

thick, dry cheatgrass overgrowing sagebrush
At first glance, Big sagebrush seems sturdy enough to stand against invasive species like cheatgrass.
However, research shows that it is particularly vulnerable to non-natives. USFWS/Jennifer Strickland

Aggressive invasives like cheatgrass start growing in the fall and early spring, and so become well-established before native grasses, flowering plants and sagebrush begin their growing seasons. Fewer native plants that are shorter and farther apart mean less of the food and cover that sage-grouse need to survive in all phases of their life cycle. 

Cheatgrass sprouts in bare ground
BLM/Antonia Hedrick

Medusahead and ventenata are other competitors. Ventenata is a more recent arrival and appears to be spreading fast. It has minimal value as forage for wildlife or livestock, and may also make the soil more prone to erosion. 

a patch of invasive ventenata grass
Ventenata grass USFWS/Jennifer Strickland

The most serious consequence of these invasive species is their effect on the cycle of wildfire in sagebrush areas. Wherever plants like ventenata and cheatgrass have replaced native species, fires tend to occur earlier in the year and more frequently. These fires can also burn more intensely and over more acres. 

Wildland fire burning in cheatgrass that has invaded sage-steppe
USFWS/Kari Greer

More frequent and more severe fires start a feedback loop that further favors invasive plants. They are able to re-grow in burned areas more quickly than native species and permanently hinder re-establishment of sagebrush and other native plants. 

dry cheatgrass that has overtaken sagebrush habitat
Cheatgrass quickly establishes in areas that have burned in wildfire. BLM/Antonia Hedrick

More than half of the sagebrush habitat lost on BLM-managed public lands between 2012 and 2018 resulted from wildfires. Burned areas can be restored, but treatment is costly and uncertain to be effective before sage-grouse and other wildlife are forced to leave the areas permanently. 

healthy sagebrush habitat with Big sagebrush, native grasses and flowering plants
Greater sage-grouse and other wildlife need expanses of intact, multi-story native vegetation for food and cover, and to ensure that water and nutrients cycle sustainably through the ecosystem. USFWS/Jennifer Strickland

The BLM manages sagebrush habitat and wildfire in tandem to conserve remaining habitat on public lands to sustain sage-grouse populations until restoration efforts are successful. 


The BLM is evaluating the plans adopted in 2015 to manage sagebrush habitat on public lands. Monitoring data and new scientific information published since 2015 will help us determine whether there are steps we should take to benefit sage-grouse and people across the West who also rely on healthy sagebrush lands. 

More stories about greater sage-grouse & their habitat  

In PROGRESS: Next steps for sage-grouse | More than the numbers | According to plan 
In BALANCE: Wildland fire | Predators 
In SEASON: Lands for a thousand dances | All the better for nesting | All in a day's walk | A year in the life | Working Winter | Sagebrush in Winter 

Heather Feeney, Public Affairs Specialist

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