In Minnesota, North Dakota and South Dakota, much of the original prairie has been lost. Recovering the benefits that prairies provide to both people and nature, including moderating floods, protecting water quality and storing carbon, is an immense and significant challenge.
The Nature Conservancy is thinking big when it comes to restoring prairie. The Conservancy’s Glacial Ridge Project in northwestern Minnesota is a great example of large-scale restoration. With 24,000 acre of newly restored, contiguous prairie, area residents are already reaping the benefits of cleaner, more-dependable drinking water, dollars from new tourism, and more. In fact, Glacial Ridge has made significant contributions to the regional economy for a number of sectors and continues to be part of a vibrant, agricultural landscape near the city of Crookston.
Prairie seed is essential to re-establishing prairie plants. To take on bigger and better restorations we need larger amounts of native seed. At Glacial Ridge, we turned to native prairie remnants to supply the seed for large restorations. On average, a 1-acre combine harvest on a native prairie yields enough native seed to plant 2 acres. This number sounds reasonable enough, but when scaled up to tens of thousands of acres, that translates to a lot of seed. At the scale of a project like Glacial Ridge, it takes nearly 300,000pounds of seed to broadcast across the land at a standard rate of 12 lbs. to the acre.
On the surface, using seed output from native prairie remnants seems like a no-brainer. It enables reconstruction of valuable landscape functions and helps reconnect habitat, which can benefit wildlife. Combine seed harvest in the fall following a spring burn can also be one of a suite of income-generating activities that prairies alone can provide. There is a robust market for high-diversity mixtures of native prairie seed in Minnesota, ranging from $25 to $45 per pound of seed. Any profits generated by these activities can help to fund future management and restoration activities.
But in recent years, land managers have raised concerns about seed collection for restoration. For example, mechanized harvest such as combining may inadvertently impact prairie soils or introduce weeds. Regardless of collection method, questions linger as to how seed harvest might change site-level plant diversity. A variety of sensitive native insects may also be at risk.
Enter Justin Meissen, a new graduate student at the University of Minnesota’s Conservation Biology Program. Meissen is an IGERT (Integrative Graduate Education and Research Traineeship) Fellow focused on introduced species and genotypes. The focus of his work is to determine whether native seed harvest is compatible with conservation goals at both the site and landscape level. His approach to the complicated topic of donor site impacts involves assessing the risks of harvest to plant diversity. This winter, he will scrutinize groups of plant traits that might render some species more susceptible than others to repeated harvesting. Over the summer, he will compare the variety of plants at several harvested sites to unharvested examples. One of the products from this four-year project will include a decision tool for land managers considering native seed harvest for a particular site. Guidance for site suitability, harvest frequency, and best practices will be provided.
Meissen is co-advised by Susan Galatowitsch and Meredith Cornett. Funding for this work is provided by the University of Minnesota, the National Science Foundation, and Minnesota’s Outdoor Heritage Fund through The Nature Conservancy’s Prairie Recovery Project.February 08, 2012