In the mid-1800s, Colorado’s Front Range forests were more open and two to three times less dense than they are today. Today, these forests have become far more dense and crowded with smaller trees which has inherently increased vulnerability to large wildfires, insect epidemics and disease. Approximately 1.5 million acres across the Front Range have been identified as needing restoration to mitigate wildfire hazard, protect communities, and restore forest structure and composition. To address this, a new guide has been produced to be used as a framework to implement place-based approaches to forest restoration.
Map of Colorado Front Range forests.
A wide-ranging group of collaborators from federal agencies, environmental non-profits, and academia, joined together to address this issue and create this synthesis of information specific to restoring these forests.
By using historical forest conditions to help guide the “desired conditions” of these forests, GTR-373 helps managers to identify areas that could benefit from restoration. It also provides an overarching framework for how to implement place-based approaches to forest restoration based on information specific to the Front Range. A companion document is also available - Visualization of Heterogeneous Forest Structures Following Treatment in the Southern Rocky Mountains (RMRS-GTR-365) allows users to “see” what the recommended treatments may look like at the stand level.
Restoration in Colorado Front Range ponderosa and dry mixed-conifer forests should result in reduction of forest densities and surface and crown fuels, enhancement of spatial heterogeneity across scales, and retention of drought-and fire-tolerant species, old trees, and structures important for wildlife. While restoration treatments are not expected to recreate the diversity of structure in the 1860s, the hope is that by pushing the stand structure of these forests back towards past conditions, they will be more resilient for the future.
Historical stand reconstruction shows that the ponderosa and mixed-conifer forests were more open and grassy than they are now, with mixed sized trees clumped together. Over time, these forests have become dense and crowded with smaller trees which increases their vulnerability to large and severe wildfires, insect epidemics, and disease.
Based on factors such as elevation and slope, the Front Range is characterized by developing a mix of low, moderate, and high-severity fire effects, making for a mixed-severity fire regime historically.
The structure and composition of the Front Range forests is shaped at multiple scales by interactions of topography, natural disturbances such as fire, and forest developmental processes. This serves as a foundation for identifying priority areas and designing restoration projects across scales.
Desired forest condition for ponderosa pine forests in the Colorado Front Range.