Prescribed Fire in Northern Colorado
and The Colorado Forest Restoration Institute
What is Prescribed Fire?
Prescribed fire is a land management tool that can help achieve land management goals. Specialists develop comprehensive plans to deliberately and safely reintroduce fire into fire-adapted ecosystems. When fire is removed from these fire-dependent systems, there can be negative consequences, including:
- Forest overcrowding and buildup of fuels (i.e. dead trees, underbrush, etc). This can be especially hazardous near communities
- Forests become easier targets and less resilient to insects and disease
- The makeup of the forest communities can be changed, as fire-adapted species are out-competed
- Habitat for wildlife can become degraded or disappear entirely for some species
- Nutrients are not returned to the soil
Fire will always be a part of fire-adapted ecosystems—communities and land managers can influence how fire is ultimately reintroduced. Fire can be returned to an ecosystem in 3 different ways:
- Wildfire: Uncontrolled and unplanned, may burn over large extent and be destructive to communities and other resources
- Managed wildfire: Natural ignitions in a predefined geographic area are allowed to burn within specific parameters to accomplish ecological objectives and reduce fire risk for neighboring communities
- Prescribed fire: experts carefully plan for ignitions and perform operations under controlled and deliberately defined conditions
“The drip torch is one of the most powerful forest restoration tools we have.”—Mike Caggiano, Research Associate, Colorado Forest Restoration Institute
Where is prescribed fire happening, and why?
Over the past few decades, the West has been experiencing catastrophic wildfire events that exceed historical fire size and severity, damage homes, and negatively impact the natural resources we all depend on. Many organizations are working to restore historical fire regimes to forested landscapes. However, wildfires do not respect agency boundaries, and the management of fire is a truly daunting task for any one organization. The recent Cameron Peak, East Troublesome and Calwood Fires had substantial ecological and social impacts that demonstrate the challenges ahead. To see how prescribed fire interacted with the Cameron Peak fire, see the video at the very bottom of this story map.
You can use the slider within the image on the left to see how destructive a wildfire can be. This is part of the Calwood Fire. Boulder, CO, 2020, 10,106 acres
In the face of this adversity, the Northern Colorado Fireshed Collaborative (NCFC) was established as a cross agency network of free-flowing information, resources, and knowledge. Made up of Federal, State, and local partners, the NCFC is aiming to restore the landscape to a more historical condition through the use of forest treatments, including prescribed fire. You can see where some of these prescribed burns have occurred in Northern Colorado, and their size relative to the Cameron Peak fire of 2020 on the left.
In the midst of this on-going conversation, the Colorado Forest Restoration Institute (CFRI) specializes in data collection, analysis, and the communication of scientific studies of forest treatments to land managers, so that future decision making is as informed as possible. This in turn will help Northern Colorado ecosystems become more resilient to wildfire, and will lessen the catastrophic effects of these events. Additionally, these efforts help refine the prescribed fire process as an effective land management tool.
Landscapes in Northern Colorado have been shaped by a long history of fire. Native cultures have been using fire long before western settlement, and Colorado State University acknowledges, with respect, that the land we are on today is the traditional and ancestral homelands of the Arapaho, Cheyenne, and Ute Nations and peoples.
Prescribed Fire aims to reintroduce this ecological process in order to mimic natural conditions, promote forest resilience, and reduce the likelihood of catastrophic wildfire.
"The relatively frequent, low- and moderate-severity components of the mixed-severity fire regime that historically characterized ponderosa pine and dry mixed-conifer forests of the Front Range are largely absent from the landscape today, due in part to active fire suppression...Loss of low-severity, frequent surface fire represents loss of a keystone ecological process responsible for shaping the structure and composition of Front Range forests." - Principles and Practices for the Restoration of Ponderosa Pine and Dry Mixed-Conifer Forests of the Colorado Front Range
Who is involved?
Several agencies in Northern Colorado are collaboratively implementing prescribed fire on the land. This includes federal, state, and local organizations such as the US Forest Service , Coalition for the Poudre River Watershed , City of Fort Collins , Larimer County, Boulder County, Northern Water , the Forest Steward's Guild among others. Because prescribed fire is such a complex issue, the sharing of knowledge, information, and operational resources is imperative to building a successful prescribed fire program. Additionally, following up on the results of these prescribed burns and their effects is crucial to maintaining clarity on what the forest conditions are before and after treatment. The Colorado Forest Restoration Institute helps achieve this through "ecological monitoring."
Prescribed Fire Monitoring
CFRI’s primary role in the NCFC is ecological monitoring of prescribed burns. Our monitoring employs field and remote monitoring techniques that capture forest conditions before and after treatments.
In this section, we'll outline some of the techniques we use to monitor prescribed fires, and then we will take a more in depth look at three of our monitoring units.
Why Monitor?
It is important to monitor treatments both before and after they occur in order to evaluate whether managers are meeting their objectives.
CFRI's Monitoring Program:
- Provides managers with an understanding of current forest conditions
- Communicates on-the-ground evidence during the project planning stage to help design treatments that achieve desired goals
- Reassesses forest conditions after treatment, and shares that information with land managers
- Is a crucial piece of the adaptive management process, as managers are able to plan future projects that incorporate newfound knowledge
In short, ecological monitoring bolsters future decision making with actionable knowledge.
A layout of CFRI's plot setup for collecting fuel and vegetative data before and after prescribed fire treatments. The gray squares above are "quadrats" (also seen in the photo on the right); field technicians estimate fuel loads (sticks, plants, and logs!) within these quadrats pre- and post-treatment.
After we collect data, we can use it in models such as Forest Vegetation Simulator (FVS). Programs like this model potential fire behavior and effects in response to treatments. For example, at this monitoring site, fire effects became less severe after mechanical thinning, and even less severe after a prescribed burn on the site.
Forest Vegetation Simulator Model
Drone-Based Ecological Monitoring
Below (and on the right) is drone imagery from the Elkhorn Unit 4 in Northern Colorado, showing differences in forest structure before and after prescribed fire. In the future, this method can be utilized by CFRI in conjunction with our on-the-ground monitoring data to better understand the effects of prescribed fire on the land and to scale up our ability to monitor at landscape scales. This powerful technology can work in tandem with data collected in the field to increase the spatial scale of monitoring and make observations of larger treatment units more accessible.
CFRI is advancing our monitoring program with the help of Wade Tinkham, a professor and researcher in the Forest and Rangeland Stewardship Department at CSU to investigate how low cost drone-based data acquisition impacts the accuracy of imaging individual trees, and other specific finer scale metrics. To learn more about this work, click here!
Field-Based Ecological Monitoring
CFRI has completed monitoring on several prescribed fire sites. The following case studies describe some results and lessons learned from these specific sites.
Ben Delatour Scout Ranch (BSR)
The Ben Delatour Scout Ranch is a significant private land holding (~3,200 acres) surrounded by other private lands and US Forest Service lands. Multiple units (smaller sections of the property prioritized for management) on the Scout Ranch have been treated through mechanical and hand thinning, and prescribed fire.
Treatment objective: to promote forest resilience to wildfire and protect water supply and infrastructure.
Boy Scout Ranch Treatment Unit
Sometimes, before putting fire on the ground, managers need to mechanically thin the forest. This is to mitigate risk of an escape into areas surrounding the treatment site. However, some areas are in a condition for prescribed fire to be applied directly, as a “first entry” treatment. When used properly, prescribed fire alone can be as effective as using mechanical treatment and prescribed fire together, but at a fraction of the cost. In the case of the Boy Scout Ranch Treatment Unit, the CFRI monitoring team got a chance to directly compare these two treatment options within a site.
In the case of this treatment unit, many of the effects of fire alone mirrored the effects of the treatment unit that had been thinned and then burned. The fire alone substantially reduced tree density to a similar level as in the unit that had been thinned, and then burned. It also significantly raised the crown base height of the remaining live trees. This means that many of the lowest branches on the trees were killed, and a future fire would have a more difficult time reaching into the crown of the tree. Generally, surface fuels were reduced in both units, and the stands became more resistant to carrying fire from tree to tree.
"The fire reduced tree density and basal area…Crown base height of the remaining live trees raised substantially and surface fuels were reduced following the prescribed burn, which increased the stand’s resistance to crown fire." - Monitoring Summary of Boy Scout Ranch burn only treatment pg. 26
Elkhorn Unit 4
This was a prescribed burn in Colorado, finished in 2019. You can zoom in and out on the map to the right for spatial context. The black dots within the polygon are where CFRI has placed on the ground monitoring plots. Additionally, in this section, you can use the slider to see what these plots look like before and after prescribed fire.
Prescribed Fire underway at the Elkhorn Unit 4.
While monitoring results can tell us what happened during a burn, they can’t always tell us exactly why, and each site will respond differently to fire based on topography, fuels, recent precipitation, moisture, and weather. Monitoring results can also be affected by the location of our plots. Sometimes the monitoring results from a prescribed burn don’t tell such a clear and concise story as at the Boy Scout Ranch Treatment Unit—this is certainly the case for the Scout Ranch Elkhorn Unit 4.
This unit contains diverse forest structures. The northern part is open and grassy, with a few trees, while the southern part is more densely forested. In the northern part of the unit, several trees were killed by the prescribed fire, but none were killed in the denser southern half. Thicker groups of trees sometimes have the effect of slowing windspeeds within them, so fire behavior is less intense. In addition, this prescribed burn was not completed, because the fire escaped and burning operations had to be halted. Ultimately, the fire burned 122 acres outside of the planned burn unit, and one shed was also burned.
There are risks around implementing prescribed fire. While the conditions under which a burn can go forward are carefully planned and monitored, weather can change quickly. However, just like we are constantly adapting our monitoring protocols to better capture variability and reality on the ground, there is extensive after-action review following such an event, and it provides opportunities to learn from what happened, and improve the next prescribed fire.
Red Feather Lakes Prescribed Burn
The objective: to promote forest resilience to wildfire and protect water supply and infrastructure.
Large treatment areas, like those possible with prescribed burns, can moderate the impact of disturbances like wildfire. Ultimately this treatment reduced the fire behavior of the Cameron Peak Fire, the largest fire in Colorado state history.
Sometimes multiple prescribed fires may be required to bring an area to desired conditions. In monitoring this burn, we learned that seasonality of burns makes a big difference when it comes to results. The first burn in March 2018 occurred in cooler weather, and snow remained on the ground on north-facing aspects, so only south-facing aspects burned. Because sections of the unit had already been burned, it was safe for a second burn in July 2019 to burn more intensely. Patches of mixed- and high-severity fire have always been part of the fire story on the Front Range, and the opportunity to return higher-severity fire to some patches of the forest increased diversity across the landscape.
Previous prescribed fires on these lands between 2008-2019 provided important fuel breaks for firefighters, and likely protected many homes and other resources. The video below describes the importance of previous prescribed fire treatments in firefighting efforts.
How Fuels Treatments Influenced the Cameron Peak Fire
Prescribed fire treatments effect the Cameron Peak Fire of 2020.
Prescribed fire is an incredibly important tool as we work to increase the pace and scale of forest restoration across boundaries. As planning tools and frameworks like PODs (Potential Operational Delineations), multi-resource focused risk assessments, and the shared stewardship approach become more integrated into decision-making, it will be crucial to incorporate prescribed fire as a way to get work done on the ground where possible. The 2020 fire season has clearly demonstrated the scale of the challenge ahead, but cross-boundary burning is already underway in Northern Colorado, and the success of these projects shows that collaborative burning can return fire to landscapes in a constructive way.
