160-Acre Expansion of Pheasant Branch Conservancy
In 2019, Dane County acquired the 160-acre Acker Parcel for $10M to restore prairie and wetlands that will “significantly reduce stormwater volume due to increased water infiltration into the ground… [and] improve water quality by reducing sediment and phosphorus runoff within the Pheasant Branch Watershed, positively impacting Lake Mendota.” This former dairy farm immediately adjacent to the northern border of Pheasant Branch Conservancy contains the headwaters for an intermittent stream into Pheasant Branch Creek and is a recharge area of Frederick Spring, presenting a tremendous opportunity for crucial stormwater management and water quality improvements.
Dane County has removed the structures on the property and begun the planning and construction of sediment basins for stormwater management, in conjunction with wetland restoration. The agricultural fields continue to be cultivated with cover crops in advance of a four-year phased conversion to native prairie.
In order to fully realize the potential ecosystem services of a restored prairie on the Acker parcel, it is crucial that the initial seeding be a high quality seed, with a high species diversity - a Platinum Prairie.
A Platinum Prairie
A high-quality prairie can be defined by its species diversity - ideally with as many as 100 plant species per acre. The deep roots of prairie grasses enhance stormwater management through improved water infiltration and groundwater recharge, but Platinum Prairies have many additional advantages over prairies dominated by a few plant species:
- The greater diversity of plant species supports a greater diversity of animals utilizing the different flora for food and habitat.
- The variety of flowering plants provide an aesthetically beautiful landscape in bloom from spring to fall.
- Greater biodiversity contributes to ecosystem resilience, better able to adapt to disturbances and changes in climate.
- A healthy prairie can provide carbon sequestration at about one ton per acre per year, with the fully-restored Acker Parcel prairie offsetting the carbon dioxide equivalent of over 16,000 gallons of gasoline each year.
- A diverse, resilient prairie will incur reduced management costs.
- Establishing a Platinum Prairie at Pheasant Branch Conservancy provides a Platinum seed collection source for future prairie restoration on other Dane County properties.
The benefits of a Platinum Prairie are significant, but they also represent a significant initial investment. Prairie seeds typically must be collected by hand; the cost of great prairie seed stock (100+ spp.) and related expenses are impressive. Starting with a Platinum seed mix is crucial; evidence suggests that later overseeding of an established prairie with a more diverse seed is ineffective.
Seed the Need: A Platinum Prairie Challenge
The Clean Lakes Alliance received a $100,000 donation from the Alliant Energy Foundation to help restore the new 160-acre parcel to prairie. The Friends of Pheasant Branch are joining forces with Dane County and the Clean Lakes Alliance to raise a matching $100,000 over 4 years to make this Platinum Prairie a reality.
Dane County Plans and Resources
Dane County's Pheasant Branch Conservancy Restoration Website
Dane County's Pheasant Branch Conservancy – 2019 Addition Property Plan