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The time is now, to get those ecological restoration projects started. The United Nations has declared this decade (2021-2030) the Decade on Ecosystem Restoration. Rangelands restoration is a focus within this effort and a parallel effort, the International Year of Rangelands and Pastoralists (IYRP) in 2026 promotes awareness about global rangelands and all who depend on them. This decade offers the best chance to bring ecosystems into a more resilient condition to withstand the impacts of climate change as it progresses.

But what is ecological restoration? The Society for Ecological Restoration defines it as "the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed." It should be noted that ecological restoration is different from restoration ecology, which is the science that supports ecological restoration practices. Within ecological restoration there is a ‘restorative continuum’ as described by Gann et al. (2019). This 'continuum' is a series of increasingly complex actions from early management actions that reduce impacts to repairing ecosystem function with rehabilitation activities to the full recovery of native ecosystems using ecological theory. Ecological restoration recovers the full composition of native species as well as the ecological processes that sustain them. A continuum of actions is necessary quite often because some landscape conditions have changed so extensively that recovery can only be achieved by various restoration approaches that target ecological processes such as reconnecting the hydrologic regime, reducing erosion and increasing infiltration, or returning fire (Palmer et al., 2016).

There are a number of natural approaches to applying ecological restoration. One called 'natural regeneration' emphasizes allowing an area where damage was low to recover naturally. This is a very cost-effective approach and can be successful when plant species remain at the site or are nearby for regeneration, there is a remnant soil seed bank, and/or habitat that remains is suitable for wildlife. If the site was more so heavily damaged, natural regeneration could take a very long time. 'Assisted regeneration' may be the better approach in areas with moderate degradation and requires some active intervention to improve the site. These active techniques may involve soil amendments/remediation, creating habitat features for wildlife, invasive species control, and/or seedling or reintroduction of species into the site. The third approach is 'assisted reconstruction' for sites that have been heavily damaged and requires the removal or reversal of the source of degradation including the reintroduction of the wildlife and plant species, where the damage resulted in an unsuitable environment for getting back the native reference ecosystem without intervention. Often, it takes a combination of all three approaches and potentially a mosaic of all three across a site. In dryland areas, techniques like 'restoration islands' (e.g., concentrated plantings in strategic locations) may be beneficial to create sources for plants to establish and spread to meet restoration goals for a site (Hulvey et al. 2017).    

From the local to the global level, ecological restoration also aims to improve human well being through restoring ecosystem service benefits as in food and water security. By restoring damaged and/or degraded lands, ecosystem function and productivity can be returned for people around the world that depend on these ecosystems for their health and livelihoods.

Invasive plants are non-native (also referred to as “alien”), and their introduction causes or could cause environmental, economic, or human health harm. Management of invasive plants is mandated by the US federal executive departments and agencies through a series of Executive Orders overseen by the National Invasive Species Council. While there are many species of invasive shrubs and trees in the US (~580) , the vast majority are forbs and grasses (>1000) (Swearingen & Bargeron, 2016). Many invasive forbs and grasses were unintentionally introduced by humans as ornamental plants for landscaping or packing materials for shipping. 

Invasive forbs and grasses compete with native rangeland plant species for scarce nutrient and water resources, while altering the existing ecosystem structure and function. Forbs and grasses become invasive beyond their native ranges due to high seed production, ability to establish in disturbed areas, extensive root systems allowing for dense growth, and/or chemical defenses against surrounding plants, just to name a few. These aggressive plant traits combined with the often remoteness of rangelands makes management of invasive forbs and grasses infamously difficult. These difficulties led to the development and implementation of an Integrated Pest Management (IPM) framework to help land owners and managers coordinate planned strategies to manage invasive plants. IPM includes many method options (biological, chemical, cultural, and mechanical) for use often in combination to target a specific invasive grass or forb to meet goals of 1) eradication of the invasive plant, and/or 2) provide resistance to (re)invasion. For more information, resources, and guidance on IPM, please see the US Department of Agriculture’s Regional IPM Centers website. 

Each invasive species must be evaluated for it’s unique biology to maximize management effectiveness. Here, we provide cases of two infamous invasive species on western US rangelands in brief. One of the most environmentally and economically impactful invasive grass is cheatgrass (Bromus tectorum). Cheatgrass, also known as downy brome, is an annual grass that has invaded much of the West and has altered historic, or introduced new, fire regimes. The extensive invasion of cheatgrass is largely due to it’s annual growth habit with germination beginning in the early spring, which leads to high density, fine-fuel accumulation during seasonal droughts for wildfire ignition and spread. Strategies for managing cheatgrass infestations often include an IPM plan with multiple methods. For example, late fall and early spring targeted grazing can help reduce seed production with backpack herbicide treatment in areas difficult to access by livestock or vehicles. Rangelands have also been invaded by the annual forb, yellow starthistle (Centaurea solstitialis), known for causing “chewing disease” in horses and dominating on high light intensity sites. Resistance to invasion and management of yellow starthistle can occur typically through an IPM framework with consecutive prescribed fires and planting/seeding competitive species to decrease light availability for reduced germination and establishment potential. 

Brush Management Workshops (series of three)

• Funded by Western SARE (Sustainable Agriculture Research and Education Program)
• Organized by Altar Valley Conservation Alliance, UA CALS Cooperative Extension and The Rangelands Partnership

Brush Management Video Series

• Brush Management Conversations: Brush Management Series - Common Ground: Cross Watershed Conversations on Finding Brush Control Solutions
• Brush Management Research: Brush Management Series - Healthy Rangelands: University of Arizona Brush Management Research
• Clara's Story: Brush Management Series - Healthy Rangelands: Future Land Stewards and Brush Management
• Gullies Damage Grasslands: Brush Management Series - Healthy Rangelands: Control Gullies, Control Brush, Save Grasslands! 
• Common Ground: Brush Management Series - Culminating Video for Workshop Series
• Common Ground: Arizona Illustrated; The Native Grassland of Arizona

Workshop 1 - Brush Management - January 22, 2018

• Invitation
• Agenda with links to presentations and videos
• Photos

Workshop 2 - Brush Management - April 19, 2018

• Invitation
• Agenda with links to presentations and videos
• Photos

Workshop 3 - Brush Management - October 4, 2018

• Invitation
• Agenda with links to presentations and videos
• Photos

Photo credit: Sarah King

No one treatment or “silver bullet” exists for managing brush on rangelands, particularly for resprouting shrub and tree species. Each brush management treatment’s effectiveness can vary widely due to weather, soil, topography, and site plant community. Additionally, land managers must weigh treatment implementation costs, environmental/cultural impact concerns, and longevity of treatment efficacy to meet their brush cover goals. 

An integrated and iterative application of multiple brush management treatments that are strategically chosen and timed based on the target shrub/tree species can potentially maximize meeting your management goals. Using an integrated approach through a Integrated Brush Management System (IBMS) allows for taking stock of current land conditions and potential resource gains, assessment of treatment options including doing nothing at all, evaluation of post-treatment efficacy, and adaptation of follow-up treatments to meet brush cover goals. The initial treatment and the follow-up treatment(s) could be very different. As an example, a mechanical treatment could be used to meet a short-term shrub cover goal but may not be cost-effective for maintenance of the shrub cover in the long-term. Following an IBMS approach (see diagram below), an alternative treatment of individual plant herbicide application could be selected and evaluated for all follow-up treatments based on cost or available funding, potential efficacy, and number of shrubs needing to treat. 

IBMS Diagram (adapted from Hanselka et al., 2001)