Greenbelt Land Trust is starting a multi-year forest thinning and habitat restoration project in Mulkey Ridge Forest at Bald Hill Farm in 2021. This project will expand and connect ecologically important oak savanna, oak woodland, and prairie habitats, decrease fuel loads and wildfire risk, and increase access for wildfire response.
Indigenous people have managed Willamette Valley landscapes since time immemorial. When Euro-American settlers arrived in the mid 1800’s, they found a lush, productive, and diverse landscape of riparian, forest, savanna and prairie habitats. The open habitats of oak savanna, wetland and upland prairie covered over one million acres. Cultural burning practices performed by indigenous people kept these habitats in an open and productive condition.
White settlement led to cultural disruption and dramatic land use changes. Indigenous cultural burning largely ended, and the fire-dependent habitats present in the Willamette Valley were severely impacted by development and lack of fire on the land. Since 1850, oak habitats have severely declined in the Willamette Valley, with less than 7% of oak woodlands and savannas remaining. The remaining oak habitats in places like Bald Hill Farm and surrounding natural areas are vital ecological treasures.
Greenbelt Land Trust acquired Bald Hill Farm in 2013 after a successful community campaign to preserve this important place for people and nature in the mid-Willamette Valley. In 2015, the adjacent Mulkey Ridge Forest property was acquired, preserving a public trail connection from Bald Hill Farm to Fitton Green Natural Area. Both properties are at the core of Benton County’s Habitat Conservation Plan, and were funded in part through the Bonneville Power Administration’s Wildlife Mitigation Program, with an agreement that restoration projects for priority prairie and oak habitats at these sites would be undertaken.
Oak savanna and woodland habitats in the Willamette Valley are some of the most iconic, culturally important, and imperiled in Oregon. They provide beauty and cultural resources to our human communities, homes for over 200 species of wildlife and birds such as Acorn woodpecker and Fender’s blue butterfly, and are more resistant to fire than the dense coniferous forests that have displaced them.
The remaining oak savannas and woodlands of the Willamette Valley are typically degraded by invasive plants and densely stocked conifers like Douglas fir. Local oral history and aerial photos document that within the last forty years the open condition of the oak savanna at Bald Hill Farm has filled in with invasive weeds, young conifers, and brush, all of which provide ladder fuels in wildfires.
Without active management, the conversion of the oak savannas and woodlands at Bald Hill Farm would continue and the habitats would be lost, replaced by a more fire-prone, less biologically diverse conifer forest. Through careful planning and selective thinning in oak habitats, the resulting forest will harbor more biodiversity while also lessening the severity and risk of wildfires.
Drought conditions in the Willamette Valley are adding to the urgency for oak restoration. Climate change is intensifying drought conditions in the Willamette Valley and conifer species like Douglas fir are seeing dramatic die-offs due to drought stress. In forests where high-density, fast-growing conifers are impacting oak habitats, fire danger is at high levels, and the opportunity to see multiple benefits from oak restoration is significant.
Greenbelt Land Trust is a member organization of the Willamette Valley Oak and Prairie Cooperative, a partnership with a sustainable, long-term vision to conserve and maintain prairie and oak habitats within the Willamette Valley. This partnership includes dozens of local, state, and federal agencies, scientists, foresters, land managers, Tribes, and conservation organizations endorsing a vision and a strategic action plan for the protection of oak and prairie habitats in the Willamette Valley.
Oak restoration projects in the Willamette Valley over the last 25 years have generated many guidelines and best practices for professional foresters and land managers. Similar projects at Baskett Slough and Finley National Wildlife Refuges, Chip Ross and Timberhill Natural Areas in Corvallis, previous Greenbelt projects at Bald Hill Farm, and many others have yielded valuable lessons and resulted in significant benefits for wildlife, recreation, and fire safety.
We are working with Trout Mountain Forestry under the guidance of a detailed Forest Stewardship Plan developed with oversight from State and Federal agencies, input from natural resources professionals, and public feedback. This project is being undertaken using best management practices with a careful, conservative approach that protects wildlife and human safety.
Conifers will be removed from around large legacy oaks, and from areas where they are overtopping and invading oak savanna, woodland and prairie. In areas that are dominated by conifers, selected thinning will be performed to manage for bigger trees, diversity, and forest health. Buffers around riparian areas will protect fragile soils and streamside habitats. Throughout the project area invasive weeds and dense understory brush will be removed to promote biodiversity and lessen wildfire danger. Snags and downed wood will be created or retained in appropriate areas for wildlife habitat. Any income generated by this project will exclusively be used for stewardship and management of the conservation values of Mulkey Ridge Forest.
This project is the third phase of oak restoration work begun at Bald Hill Farm in 2015, and continued in 2016. Treatment of invasive species in the project area will take place in mid-April and will result in short term closure of the trail from Fitton Green Natural Area to Bald Hill Farm. Construction of an extension of the gravel road through Bald Hill Farm is scheduled for May. The road will provide permanent access to the forest for ongoing management and wildfire response. Construction of the road is downslope of the trail and will not require trail closures.
Tree removal and related project work will start after July 15th to allow for the conclusion of nesting bird season. The trail from Fitton Green Natural Area to Bald Hill Farm will be closed for the duration of this phase of the project. The trail closure will be clearly marked. For your safety, please follow the trail closure and do not proceed past the signs or enter the project area. Heavy equipment and trucks present extreme danger to trail users.
Greenbelt and Trout Mountain Forestry will follow all applicable laws and regulations for safe forestry operations, including Industrial Fire Protection Level restrictions and guidelines. We are carefully considering community safety during operations. Delaying the start of the project until July 15th means that shutdowns during fire season may be more likely to occur, which would also lengthen the trail closure period. Heavy equipment operation and tree removal work in 2021 will continue into the fall until weather and site conditions end this phase. Later in the fall, tree tops and limbs will be burned in a permitted and regulated slash burning operation.
There are two planned phases for this project, with the second phase in 2022 following the same timeline as above. Invasive weed and brush mowing and removal will continue in the project area on an ongoing basis.