Pollinators are declining in the Great Plains, largely due to loss and degradation of native habitat. Given this decline, and the beneficial impacts that pollinators can have on crop production and the resilience of native habitats, it is critical and urgent that we understand the relationship between floral resources, pollinators, and prairie restoration techniques. However, there are significant knowledge gaps regarding the relative benefits that different grassland plantings and their management offer to pollinators and the floral resources that support them. It is also uncertain how different restoration techniques and management impact the economic and ecological trade-offs made by farmers, ranchers, and the conservation community interested in conservation grassland programs such as the CRP, which purportedly support pollinators but have undergone little formal assessment. As such, we designed an experiment with the City of Lincoln, Nebraska (“City”), to compare floral resources offered by different grassland planting methods within a large, public green-ways project, the Prairie Corridor (“Corridor”).
Titled “Increasing the effectiveness of pollinator conservation grasslands within the tallgrass prairie region”, this project is entering it’s second of three years and is comparing the floral resources available for the local bee community from two types of restoration, a high-diversity mix, and mid-diversity pollinator-specific mix. We planted 24 1-acre plots in April 2019 (eight each of high-diversity, mid-diversity, and control), and further randomly assigned half the common grassland management method of mowing, and collected data on plant community composition, the timing, quantity, and diversity of floral resources. We will add data on bee visitation rates for 2020 and 2021.
As this proposed study is within a multi-million dollar, high visibility public project, it is ideally situated to partner with multiple non-academic stakeholders on research relevant to farmers, ranchers, and communities in the Great Plains. These include the USDA-NRCS Nebraska, the Xerces Society, Prairie Legacy, Inc., Prairie Plains Resource Institute, LLC, and the City of Lincoln. These organizations work with broad audiences, including many farmers and ranchers with land conservation goals and are ideally positioned to offer them recommendations based on the proposed research. The City also has project outreach strategies and outlets in place, and as such is the ideal partner to assist in communicating lessons learned from the proposed research.
Project objectives from proposal:
This project was designed for two audiences: the conservation community restoring native tallgrass prairie in the eastern Great Plains (Lincoln City Parks and other parks, preserves, natural areas) and farmers and ranchers planting grasslands that provide pollinator resources (the Conservation Reserve Program or “CRP”, hay meadows, etc.). In 2016, President Obama established the National Pollinator Health Strategy and pollinator habitat became a priority for working grassland programs like the CRP. Agencies spend close to $100 million per year on grassland-related conservation on private lands in Nebraska. Currently, we use lists of plants potentially favored by pollinators, particularly wild bees, when developing prairie seed mixes, but little data exists on how bees use those resources, and how seed mix and management may affect bee usage.
In other words, we poorly understand the return on society’s $100 million dollar investment in grassland conversation in Nebraska. Although high diversity prairie restorations are usually expensive (>$500 per acre), seed mix cost per acre varies widely. As such, this project will help land managers and conservation professionals balance the trade-offs between high establishment costs and high payoffs in terms of pollinator habitat, leading to powerful learning outcomes for both of our audiences. The first expected action outcome is that the City can apply this project’s new information when designing seed mixes for hundreds of acres planned for restoration within the Corridor, with other professionals following suit as information is disseminated to landowners through City outreach and collaboration with the NRCS and The Xerces Society.