Invasive Species
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Overall, indaziflam + imazapic had greater initial control of cheatgrass, but by 2023, both treatments led to similar ∼17 percentage-point reductions in cheatgrass cover. Cheatgrass individuals that “escaped” the herbicide treatment grew exceptionally large and fecund. There were no reductions in cover in any native vegetation type, including biocrusts, and nontarget increases in cover were observed for 1) deep-rooted perennial grasses treated with indaziflam + imazapic in the 2011 burn subregion and 2) the shallow-rooted Sandberg bluegrass (Poa secunda) treated with either herbicide in the 2011 or 2011 + 2019 burn subregions. Consideration of burn legacies, pretreatment landscape condition, and evenness of treatment application may improve restoration outcomes and help prioritize management allocation, timing, and treatment expectations.
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Invasives Free USA is a new campaign focused on protecting our favorite places from invasive species. Inspired by the Predator Free 2050 program from New Zealand, this campaign requires local engagement and organization to prevent and control invasive species. This presentation will highlight examples at local, regional and national levels where landowners are creating invasive free zones in the United States – and you can too!
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Our research shows that across deserts, grasslands, and forests, plant communities with higher abundance of naturalized species are more acquisitive above and belowground, shorter, more shallowly rooted, and less dependent on mycorrhizal symbionts for resource acquisition. These functional shifts likely drive observed changes in carbon storage, litter decomposition, and nutrient and water cycling in invaded ecosystems. This mechanistic understanding of functional community change is a crucial step toward predicting and mitigating impacts of naturalized and invasive species.
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Using the Gunnison sage-grouse as a case study, we leveraged existing resource selection function models to identify areas of high restoration potential across landscapes with variable habitat conditions and habitat-use responses. We also tested how this information could be used to improve restoration planning. We simulated change in model covariates across crucial habitats for a suite of restoration actions to generate heatmaps of relative habitat suitability improvement potential, then assessed the degree to which use of these heatmaps to guide placement of restoration actions could improve suitability outcomes. We also simulated new or worsening plant invasions and projected the resulting loss or degradation of habitats across space. We found substantial spatial variation in projected changes to habitat suitability and new habitat created, both across and among crucial habitats. Use of our heatmaps to target placement of restoration actions improved habitat suitability nearly fourfold and increased new habitat created more than 15-fold, compared to placements unguided by heatmaps. Our decision-support products identified areas of high restoration potential across landscapes with variable habitat conditions and habitat-use responses. We demonstrate their utility for strategic targeting of habitat restoration actions, facilitating optimal allocation of limited management resources to benefit species of conservation concern.
This special issue of Rangeland Ecology and Management is dedicated to applying the Sagebrush Conservation Design (SCD) to improve conservation outcomes across the sagebrush biome in the face of pervasive ecosystem threats.
Articles included:
State of the sagebrush: Implementing the Sagebrush Conservation Design to save a biome
Closing the conservation gap: Spatial targeting and coordination are needed for to keep pace with sagebrush losses
Climate change amplifies declines in sagebrush ecological integrity
Well-connected core areas retain ecological integrity of sagebrush ecosystems amidst overall declines 2001–2021
Spatial prioritization of conifer management to defend and grow sagebrush cores
A strategic and science-based framework for management of invasive annual grasses in the sagebrush biome
Modeling cropland conversion risk to scale-up averted loss of core sagebrush rangelands
Characterizing wildfire risk for the Sagebrush Conservation Design
An assessment of conservation opportunities within sagebrush ecosystems of US National Parks and Wildlife Refuges
Tool to promote stepping down the Sagebrush Conservation Design to local conservation planning
Exploring the sage grouse initiative’s role in defending and growing sagebrush core areas
Satellite remote sensing to assess shrubland vegetation responses to large-scale juniper removal in the northern Great Basin
Cooperative conservation actions improve sage-grouse population performance within the bi-state distinct population segment
Evaluating the Sagebrush Conservation Design Strategy through the performance of a sagebrush indicator species
How a Sagebrush Conservation Strategy benefits rangeland birds
Carbon Security Index: Novel approach to assessing how secure carbon is in sagebrush ecosystems within the Great Basin
Using technical transfer to bridge science production and management action
Assessing conservation readiness: The where, who, and how of strategic conservation in the sagebrush biome
Where do we go from here with sagebrush conservation: A long-term perspective?
There is no hope without change: A perspective on how we conserve the sagebrush biome
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Abundances of dominant invaders, cheatgrass and Russian thistle, were measured along treated and neighboring untreated edges in 40 paired plots along ∼61 km of 60-m wide fuel breaks. Fuel breaks were constructed using a variety of shrub-cutting and herbicide applications 1–4 yr before measurement. Generalized linear mixed effect models revealed that fractional cover significantly increased in treated compared with untreated areas by 0.02–0.12 for cheatgrass and 0–0.06 for Russian thistle within 9 m of treatment boundaries (on a scale of 0-1). We neither detected increased invasion in adjacent and untreated areas nor gradients of increasing invasion with proximity to treatment boundaries. Although these findings reveal invasions that were otherwise undetected across the entire 60 m width of fuel breaks, invasion levels did not surpass nominal management thresholds for fire behavior or risk of conversion to annual grasslands.
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Save the date for the 2025 SRM Annual Meeting in Spokane, WA.
February 9-13, 2025
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Fire is an integral component of many Southwest ecosystems; however, fire regimes across the region have been affected by climate change, creating conditions to which these ecosystems have not adapted. Since 1980, fire frequency, size and severity have increased in many ecosystems in the western US due to changes in climate combined with a history of fire suppression and other forest management practices, such as grazing and logging…
…The goal of this synthesis is to provide a summary of the literature, published in 2023, on fire and fire-related topics
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We combined predicted susceptibility with burn probability to quantify the 10-year total risk of cheatgrass dominance. Finally, we identified portions of the landscape (1) at risk of fire-induced conversion to cheatgrass dominance, (2) consistently susceptible to cheatgrass dominance, or (3) consistently resistant to cheatgrass dominance. At the scale of the sagebrush biome, we found that abiotic susceptibility to cheatgrass dominance drives total risk, regardless of fire. At local scales (i.e., individual 30 m pixels), burning increased the probability of cheatgrass dominance by a median of 14 %. Threshold-based analyses indicate that 10–31 % of the sagebrush biome was at risk of fire-induced dominance, with 55 % exhibiting abiotic resistance and 5 % exhibiting abiotic susceptibility to dominance regardless of fire. Burn probability was higher in areas predicted to be susceptible to dominance, illustrating how cheatgrass invasion can cause ecosystem conversions that are then sustained by grass-fire cycles. Disentangling the influence of abiotic conditions and fire contributes to our understanding of the mechanisms driving invasion dynamics, and modeling the probability of dominance can help anticipate where ecological transformations are at risk of occurring. Our approach can facilitate the prioritization of management actions in the sagebrush biome and be used as a framework for modeling invasion risk in other disturbance-prone ecosystems.
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This webinar for land management practitioners goes deep on subjects like wildfire prevention, rangeland restoration, and invasive vegetation treatments.