Management Plan: Carolyn Holmberg Preserve at Rock Creek Farm

Stearns Lake

Vision: Carolyn Holmberg Preserve at Rock Creek Farm is a working landscape of farming, ranching, irrigation features, and reservoirs, intertwined with critical wildlife, wetland, riparian, and grassland habitats, that preserves its distinct history and provides regional trail connectivity and recreational amenities for current and future generations.

The Board of County Commissioners approved an updated management plan for the Carolyn Holmberg Preserve at Rock Creek Farm (CHP/RCF) open space in January 2021. The plan provides direction to staff on management of the property, which involves the wide variety of resource activities that reflect the department’s mission to conserve natural, cultural, and agricultural resources and provide public uses that reflect sound resource management and community values.

CHP/RCF is located along US Highway 287 and Dillon Road and encompasses 1,124 acres. Beginning in 1980, Boulder County purchased CHP/RCF to provide an open space buffer between surrounding communities and preserve the property’s cultural resources and agriculturally significant lands. Boulder County Parks & Open Space (BCPOS) leases much of the property to an agricultural operator who raises irrigated and dryland crops, as well as livestock, on agricultural lands of national and local significance. Other portions of the property are leased to the Birds of Prey Foundation rehabilitation center.

CHP/RCF is one of the most visited parks in the entire BCPOS system. The Rock Creek regional trail and Stearns Lake attract visitors who primarily enjoy biking, hiking, and fishing activities. Today, the open space sees over 75,000 visits annually.

The approved management plan emphasizes the area’s multiple resource values and uses, provides for continued agricultural production, protects the most sensitive natural, cultural, and historic resources, allows for appropriate visitor uses, and utilizes an adaptive management approach. Key components of management are as follows:

Improving Prairie Dog, Burrowing Owl, and Agricultural Management

Prairie dog management designations will be unchanged, except for a 40-acre burrowing owl preserve located in the north part of the property. It will be designated to support active agricultural operations. Prairie dogs and grassland restoration will be emphasized in the southern and western part of the property to more effectively manage areas where burrowing owls have nested in recent years. Cultivated agriculture operations will be removed from this area to create more contiguous acres and reduce habitat fragmentation.

Restoring Grassland and Riparian Health

The health and ecosystem function of grasslands will be improved through refined management of prairie dogs and livestock grazing. A priority within riparian corridors is preserving wildlife habitat and plant communities. Grazing in riparian areas will be planned and executed to improve and maintain wildlife habitat and native plant communities.

Recreation Management for Wildlife and Visitors

Several species of raptors utilize CHP/RCF for nesting, roosting, and hunting, including bald eagles and burrowing owls. Seasonal closure of the regional trail limit disturbance to breeding activities. The updated plan includes trail improvements to provide alternate routes and a safe regional trail connection during these closures.

Cultural and Paleontological Resources

CHP/RCF is rich in cultural and paleontological resources. Although known sites that need protection exist, a survey of the entire property has never been done. Additional surveys, an analysis of paleontological resource potential, and procedures to protect resources from impacts due to the property’s use are recommended and will guide future actions for preserving these resources.

An outcome of the CHP/RCF management plan is a list of implementation activities. These action items will be initiated as funding becomes available. The time frames outlined coincide with the POS Improvement Program, a rolling five-year program currently addressing fiscal years 2021-2026. Please visit boco.org/CHPplan to learn more and read the updated plan.