Community Agriculture Alliance: What to expect from pine beetle epidemic impacts
June 3, 2011
Steamboat Springs — The shade and cover of Colorado's high mountain forests helps regulate snowmelt while ensuring a steady supply of water for consumption, agriculture and recreation. Clean water is one of the important benefits of forest systems, and many local residents have expressed their concern about the state of our local forests in the wake of the mountain pine beetle epidemic. Specifically, people are concerned as to how the ecosystem will function after the mountain pine beetle epidemic has run its course, and what the forest will look like in the future.
According to the Colorado State Forest Service's 2010 Report on the Health of Colorado's Forest, "Continuing Challenges for Colorado's Forests: Recurring & Emerging Threats," the number of acres statewide showing active beetle infestation has dropped below the previous year's levels for two years in a row. This is primarily because of host depletion in Grand, Jackson, Routt and Summit counties. The beetles have simply run out of food and are moving east. We're now dealing with the problems associated with the many thousands of dead trees in our forests and actively managing to mitigate the impacts of this outbreak while helping to speed up the re-establishment of the forest.
It's important to remember that the ecology of the lodgepole forest has evolved around disturbances such as fire, and the species is adapted to take advantage of the large openings that result from catastrophic events. The scale of the current epidemic may be unprecedented, but it is not unusual historically to have large areas of lodgepole pine die at more or less the same time within a landscape. The key concern is that now we live within these landscapes and many of the effects of the epidemic potentially affect us, and, to some unknown degree, species that are dependent on mature lodgepole forests. The impacts and issues that we are addressing include but are not limited to: hazard tree mitigation; fuel reduction around communities and critical infrastructure; using local wood for sustainable local businesses and reducing the costs of treatments; mitigating impacts to recreation and tourism; wildlife habitat concerns; and watershed protection.
The Colorado State Forest Service developed a Colorado Statewide Forest Assessment and the Colorado Statewide Forest Resource Strategy in 2010 to address these and other recognized threats to the forest. The Colorado Statewide Forest Resource Strategy identified opportunities for collaboration with cooperators and stakeholders in the implementation of these strategies. Currently, a significant part of the work of the CSFS focuses on wildfire prevention and suppression and the wildland-urban interface. These are areas where forest management practices can significantly mitigate threats. For example, fuel reduction, stand thinning and timely harvest of mature forests can reduce the impacts of catastrophic wildfires or further insect and disease outbreaks. Furthermore, most lodgepole pine stands that have survived this outbreak consist of younger trees, generally those less than 40 years old, many of which developed after harvest treatments in the recent past. These observations give us confidence that forest management is necessary if we are to continue to help mitigate for a century of fire suppression and the more recent mountain pine beetle outbreak, as well as to help shape the future forest. We hope to diversify the age class and species composition of our new forests to make them more resilient to future threats.
So what will the new forests in our area look like? Spruce, fir and aspen obviously become a more significant component of our forests in Routt County, at least in terms of percentage of mature forest. We are seeing strong natural regeneration of lodgepole forest where harvesting has taken place, and the rapidly growing young lodgepole will quickly become more noticeable on the landscape. We also are seeing aspens filling in some of these areas. Aspen may be the real winner out of this epidemic and could help address the lack of young aspen regeneration common to the forest in Routt County. Rates of decay are slow in the dry climate of Northwest Colorado, therefore, beetle-killed and wind-thrown trees will remain for many years. Every year will see more of the trees killed in the epidemic falling to the forest floor. Fire will inevitably shape at least a portion of the post-epidemic landscape. As our understanding of forest dynamics post-outbreak keeps growing, the Colorado State Forest Service will continue to provide technical expertise and resources, working closely with landowners who care about sustainability and the resilience of our natural resources.
The strategy and assessment are available at http://csfs.colostate.edu/pages/statewide-forest-assessment.html. The health report is available at http://csfs.colostate.edu/pdfs/FINAL_2010_Forest_Health_Report_www.pdf.
Carolina Manriquez Espinoza is a forester with the Colorado State Forest Service, Steamboat Springs District.