This section explores the science behind the restoration of sagebrush ecosystems. Scoll down the page to read each sub-section, or click the Science drop-down navigation to go directly to a sub-section.
The combination of management zones, Priority Areas for Conservation (PACs), and landscape cover of sagebrush provide an initial means to identify and prioritize areas for restoration and management strategies.
Prioritizing landscapes/locations for restoration should use:
Sage-grouse populations will benefit more from restored habitat inside PACs (cross-hatched areas in the graphic) than from restored habitat within the current sage-grouse range, but outside PACs (uniform gray areas in the graphic). Restoration efforts that take place in either of these designated landscapes (within PACs or within the current range) will benefit sage-grouse more relative to restoring areas outside the current range (Pyke et al. 2015b, Figure 1).
Figure 1: Click on map for a printable PDF version.
Areas of highest grouse density can be priorities, versus those with lower densities, since sage-grouse have a very highly clustered distribution. For an example, see Doherty et al. (2016), Figure 10.
Figure 10: Click on map for a printable PDF version.
Resilience to disturbance increases with cooler soil temperature and with wetter soil moisture regimes. Revegetation successes also tend to increase along similar gradients. This figure from Chambers et al.(2017), Figure 6, shows how these gradients are spatially explicit and can be mapped. Areas with high or low temperature and moisture regimes can be compared and the corresponding likelihood of restoration success predicted.
Figure 6: Click on map for a printable PDF version.
Landscape cover also includes native perennial grasses and forbs, but sagebrush is easily detected with remote sensing equipment and provides a surrogate for the community as a whole. Most importantly, sage-grouse population lek persistence is related to sagebrush landscape cover. For example, this map (Pyke et al. 2015b, Figure 5) shows variation in sagebrush cover across the range.
Figure 5: Click on map for a printable PDF version.
Human disturbance is strongly negatively associated with sage-grouse occurrence and persistence (see Knick et al. 2013 and the Conservation Issues Lesson).
Avoidance of anthropogenic stressors (habitat fragmentation, pollution, introduction of exotic species, croplands, Interstate highways and roads, energy development [wells, wind towers], mining sites, communication towers and transmission corridors, urban development) should be factored into selecting restoration sites in order to increase the probability of success.
To appropriately avoid human disturbance, it is recommended that disturbance buffer distances, such as those defined in Manier et al. (2014), Table 1, be incorporated in locating restoration sites.
Many of these factors can be combined into the sage-grouse habitat resistance and resilience matrix, which combines sagebrush cover of landscape and resilience to disturbance/resistance to invasive annual grasses (Chambers et al. 2016, Table 8). See the lesson on Resistance & Resilience for more detail on this table.
Open the graphic to view information about this matrix.
Breeding Habitat Matrix
When should you use reseeding or transplanting techniques? Click Play to listen to Jay Kerby discuss seeding and plugs.
Click Play to listen to Tony Svejcar discuss the benefits of bunchgrass.
Because seed size may vary among species, seeding depth is commonly an important factor relating to seeding success (Hardegree et al. 2011). Recommended seeding depths by species are reported in Monsen and Stevens (2004). Depth bands are commonly applied to drills to insure the appropriate seeding depth is achieved and should be used as a best management practice when seeding species in sagebrush steppe ecosystems. They are also used to minimize soil disturbance to create minimum till drills. Multiple seed boxes that feed seeds of different sizes or with appendages (for example, awns and plumes) into different seed tubes on drills may be necessary to seed species that require different depths or further mixing to pass through seeding tubes. Forbs are important for sage-grouse brood rearing and should be included when possible on restoration projects when they are known to be missing from the ecosystem.
To better understand how and where to restore degraded sagebrush landscapes, Arkle et al. (2014) measured Greater Sage-Grouse occupancy at survey sites across the Great Basin to compare sites that were burned by wildfire, but untreated with any restoration technique; burned and seeded; and unburned and untreated. They found the following relationships:
Invasive species are addressed more fully in topic 4 (Systems Invaded by Annual Grasses); however, cheatgrass, medusahead, and North Africa grass re-establishment remains an ongoing challenge to restoration efforts. Monaco et al. (2016) conducted a meta-analysis of various treatment methods used to discourage cheatgrass (Bromus tectorum) re-establishment from seed banks.
The results from the meta-analysis are illustrated in the graph (Monaco et al. 2016, Figure 12.3). Specifically:
Next explore the Land Management Tools section to learn about tools for restoration of sagebrush ecosystems.