Promoting Resilient Forests in Colorado
Promoting Resilient Forests in Colorado
Forest management must match the increasing pace of wildfire risk
Healthy forests support wildlife, improve water quality, clean the air, provide space for recreation, supply sustainable wood products and create jobs that boost local economies.
Decades of fire suppression and a changing climate have disrupted Colorado’s natural wildfire cycles and threaten the resiliency of our forests. Colorado’s forests evolved alongside low severity fire, and active management can ensure forests are more resilient to fire by making wildfires less severe when they occur. Low severity fires help manage forest density and compositions, especially in dry ponderosa pine forests that are common across the state. Extreme wildfire burns hotter and longer, potentially leading to the landscape converting from forests to other non-forested ecosystems (Coop et al., 2020).
Intense fires can destroy plants, damage soil, and put watersheds, communities and ecosystems at risk. Active management is critical to create resilient forests, keep wildfires at a low severity and ensure these values are protected.
Managing forests by reducing fuels
Wildfire fuel can be any ignitable material, such as grass, twigs and larger diameter vegetation.
Severe wildfires are prompted by dense vegetation, strong winds, dry conditions, fuel moisture and ignition risk. While we can’t control the weather, we can reduce the amount and arrangement of fuel available in forests to keep wildfires less destructive when they occur. This can also create opportunities to successfully suppress wildfires to protect homes and property.
Healthy forests can recover from disturbances like insects, disease, wildfire, floods and drought. Forests with a mix of tree ages, densities, species and adaptations are naturally more resilient. Dense, uniform forests can be slower to recover from disturbances. The risks of wildland fire are greater than ever, as Colorado’s forests are dense with heavy dead vegetation from insect outbreaks, drought and environmental factors (Hagmann, 2021; Hessburg et al., 2019; Prichard et al., 2021).
As Colorado’s lead agency for forest management and wildfire risk mitigation, the Colorado State Forest Service helps landowners and communities manage their forests. This includes guidance for Community Wildfire Protection Plans (CWPPs) and active management actions, such as fuel breaks, that reduce wildfire risk.
Foresters and wildfire staff collaborate across public and private lands, connecting communities, landowners and federal partners to improve forest health and apply effective fuels treatments.
Prioritizing wildfire resilience
When weighing management decisions, wildfire risk mitigation is a top priority in Colorado to potentially reduce the impacts of severe wildfire.
The success of management efforts can be measured by the number of homes protected, recreational areas preserved, long-term carbon storage or other ecological goals (Vorster et al., 2024). Success should be viewed within the specific context of a project. No single project will be able to address every value we find important in Colorado but can be linked with others to push broad landscapes towards desired future conditions. For example, a project aiming to protect a watershed from high-severity crown fire can be located adjacent to home hardening projects. Both projects have different primary intentions but result in a range of benefits to the landscape.
Caring for our forests means balancing environmental and community needs while taking proactive steps to keep forests healthy and resilient for a changing climate (Davis et al., 2024; Prichard et al., 2021). Balancing these trade-offs is key when making land management decisions. There are no quick fixes for issues impacting Colorado forests. Carefully considering the context of each project informs the best actions and decisions.
For Colorado’s growing population in the wildland-urban interface, living with wildfire is a year-round reality. Since 2001, the state has experienced 20 of its largest fires, with 15 of those in just the past nine years. Without action, forests will continue to face severe and unpredictable wildfires, risking their ability to stay as forests and continue to provide valuable ecosystem services.
At the state level, programs like the Colorado Strategic Wildfire Action Program help reduce wildfire risk by funding workforce development, landscape resilience and wildfire mitigation. The Forest Restoration and Wildfire Risk Mitigation grant program funds community-led wildfire mitigation for high-risk areas, along with capacity-building opportunities for grantees.
Forest treatments
Forest treatments are management actions designed to fit the unique conditions of each area – there is no one-size-fits-all solution.
With 24 million acres of forests in Colorado, management road maps like the 2020 Colorado Forest Action Plan focus on ongoing conditions and trends across the state. This informs strategic acres, with the goal of treating 10% of the state’s forests that are in most urgent need of treatment to improve resilience.
Foresters first assess the landscape to determine the most effective treatment methods. Even within the same forest type, different sections may require different approaches. This can be based on factors like slope, past management, wildlife habitat, recreation, communities and threats from disturbances like insects and diseases.
Effectiveness of fuels treatments
Fuels treatments can include removing trees, planting trees, prescribed burning and slash pile burning to reduce fuels. Fuels thinning – with machines or by hand – usually refers to the removal of small diameter trees to reduce forest density, mimicking the way wildfire typically causes small trees to burn (Fulé et al., 2012). Fuels thinning reduces ladder fuels, which are small trees or other vegetation that allow fire to climb from the ground into the canopy. Thinning also helps protect mature trees, making forests more resilient to wildfire (Bernal et al., 2023; Knapp et al., 2021).
Foresters often work in dry pine and mixed-conifer forest types, where the combination of thinning and prescribed burning are shown to be the best management actions for lowering wildfire severity into the future (Hagmann et al., 2021; Hood et al., 2024). These treatments reduce surface fuels and open tree canopies. Across different forest types, they can reduce wildfire severity by up to 72% compared to untreated forests (Davis et al., 2024, Kennedy et al., 2014).
These approaches align with indigenous land stewardship principles, which emphasize balancing forest resources – such as wildlife habitat and foraging areas – while using prescribed fire to maintain healthy, productive forests (Lake and Christianson, 2019).
Insects, wildfire and fuels
Insect outbreaks, like those caused by bark beetles, do not necessarily increase wildfire risk in Colorado. Wildfire behavior is primarily driven by climate factors like drought and high temperatures. Outbreaks can temporarily change fuel dynamics, especially during drought, that vary across stages of tree needles turning from green, to red, to gray as they die.
The overall impact of insect outbreaks on wildfire risk or severity depends on factors such as outbreak timing, forest types and weather conditions (Mietkiewicz and Kulikowski, 2016; Harvey et al., 2014; Jenkins et al., 2008; Andrus et al., 2016; Talucci and Krawchuck, 2019; Hart et al., 2015).
Success in action
Research shows that fuel treatments can reduce crown fire severity for up to 20 years before follow-up maintenance is necessary (Brodie et al., 2024). Forest treatments also lower burn severity in large wildfires, as seen in the Cameron Peak Fire of 2020, which burned over 320 square miles. Trees in treated areas were more likely to survive, and the treatments improved access for first responders (Vorster et al., 2024).
In July 2024, an abandoned campfire sparked the Wellington Fire, near Breckenridge, Colo. The fire started within the recently completed 90-acre Wellington Fuels Reduction and Forest Health Project, which helped firefighters quickly contain it to just one acre, despite windy and humid conditions. With less fuel available, the fire remained as a low-intensity ground fire, instead of climbing into tree canopies at a higher severity.
It’s not just luck – this project highlights how proactive forest management and agency collaboration can make wildfire suppression more effective, especially when communities are at risk. Fuels treatments are a crucial part of ushering in healthier and more resilient forests that will benefit future generations.
References
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