Sometimes, looks can be deceiving. That is certainly true when dense stands of overly mature trees suggest a healthy landscape. In reality, those forests may need help. This summer, Pitkin County Open Space and Trails is working independently and with other land managers to provide that aid in several locations. We’re regenerating vegetation by cutting it down.
It may sound counter-intuitive, but in the absence of natural forest fires to reset the clock on a forest’s growth, species such as Gambel oak grow past their prime. Prescribed burns or the mechanical cutting of trees are alternative ways to rejuvenate vegetation and, in turn, maintain a diverse habitat that provides forage and movement corridors for wildlife. Such efforts also help reduce the potential for destructive wildfires by eliminating areas of old, decadent vegetation.
The first project of the season is already complete. Within a short, two-week window in May – between snowstorms and important bird-breeding seasons – a contractor was able to complete about seven acres of vegetation thinning on a portion of Red Butte Ranch Open Space to improve wildlife habitat and forage, and also reduce fire fuels. The area is located to the northeast of Stein Park. The next phase of this cross-boundary effort will be a similar vegetation project on adjacent private lands. The Aspen Fire Department spear-headed this work, brought participating parties together and secured the funding to make it happen.
Still to come on Open Space are projects at both Sky Mountain Park and Filoha Meadows Nature Preserve – properties that each have seen vegetation treatments previously. Open Space and Trails has contracted with Western Vegetation Management to complete more than 100 acres of vegetation thinning on the two open spaces this summer and early fall. Both projects are expected to begin in August.
At Sky Mountain Park, 105 acres were identified for mechanical thinning in 2014, but the steepness of the slopes limited the actual project to roughly 70 to 75 acres. At that time, a mosaic of decadent Gambel oak was cut by a machine that grinds and shreds, or masticates, the vegetation. The thinned areas quickly became difficult to pick out as new vegetation sprang up – an indication of success (see the photo of the project area, taken a year after the 2014 work). Post-project monitoring in 2017 and 2018 documented regenerated stands of palatable oak, a greater diversity of plant species in the masticated zones and an increase in foraging mule deer, elk and black bears within the areas.
Nine years after that success, it is time to create another mosaic of disturbance on the landscape. This year, an additional 45 acres at Sky Mountain Park are targeted for thinning, including some of the steeper areas that were not reached in 2014. The work will involve a hybrid approach using machinery and follow-up hand crews to cut areas unreachable by machine. Again, Gambel oak and chokecherry are the target species; both regenerate quickly from their roots.
Vegetation management has also been an ongoing effort in the Crystal Valley, both at OST’s Filoha Meadows Nature Preserve and on national forest lands. Numerous mechanical treatments have occurred in the valley since the 2011 approval of the Aspen-Sopris Wildlife Habitat Improvement Project – a large, multi-year U.S. Forest Service project to improve habitat and browse for bighorn sheep, mule deer, elk and other wildlife.
At Filoha Meadows, the last mechanical treatment was in 2013. In 2016, the U.S. Forest Service conducted a prescribed burn on the hillsides east of Filoha that also stretched to the edge of the meadow. This year in August, about 60 acres in two pockets – one dominated by oak brush and one of piñon-juniper – will see mastication and/or hand thinning.
In addition to improving elk forage in the oak shrublands, the Filoha project targets piñon-juniper to benefit bighorn sheep by improving sightlines and escape routes for sheep that frequently descend from the rocky outcrops above into the meadow to forage.
Open Space and Trails is collaborating with the Forest Service and Colorado Parks and Wildlife on this cross-boundary project, which will touch both the open space and the national forest.
- By Pitkin County Open Space and Trails