2018 Farm Bill Contains Conservation Practice for Prairie Strips

2018 Farm Bill Contains Conservation Practice for Prairie Strips

It always seems that it takes time to figure out the details that are included in large pieces of legislation, and the 2018 Farm Bill is no exception. One of the important conservation practices added to CRP, prairie strips, will benefit both water quality and wildlife.

Iowa State University (ISU) has been conducting research on prairie strips for over 10 years. The STRIPS project (Science-based Trials of Rowcrops Integrated with Prairie Strips) is a long-term, interdisciplinary agricultural research project led by ISU. The project aspires to determine how integration of strips of native prairie vegetation into agricultural landscapes can provide benefits to agriculture and wildlife.

These prairie strips can be found in the form of contour buffer strips and edge-of-the-field filter strips. Prairie strips are usually 10 percent or less of the crop field and can yield some of the same benefits of native prairie fields. Prairie strips yield greater benefits than other perennial vegetation because of the diversity of native plant species, deep root systems, and stiff, upright stems that contribute to slowing surface runoff and holding the soil in place.

Research from Iowa State shows that by converting 10 percent of a crop-field to diverse, native perennial vegetation, farmers can reduce sediment movement off their field by 95 percent. These 15-foot to 30-foot strips of prairie along the contour allow farmers to reduce phosphorus loss by 90 percent and reduce nitrogen in surface water by 91 percent. They also substantially increase biodiversity in the row crop rotation.

The strips are usually composed of approximately 30 species. The native species mixes are comprised mostly of wildflowers and three to five grass species. The prairie strip treatments have four times the amount of native plant species diversity, two times the native bird abundance and 3.5 times more native pollinators.

Bird abundance was 71 percent higher in fields with prairie strips than conventional fields studied by Iowa State. However, diversity and richness were similar across all land covers. This is likely due to the strong response of a few species [e.g., Red-winged Blackbirds (Agelaius poeniceus), Dickcissels (Spiza americana), and Common Yellowthroats (Geothylpis trichas)] to prairie strip installations. Dickcissels responded the strongest and were three times more abundant in fields with strips. Prairie strips do not seem to act as ecological sinks as other ongoing research has shown that birds nest in higher densities and experience higher nest survival in strips compared to other grassy features on farms.

Farmers and landowners can blend conservation practices with production agriculture to be part of the solution. Prairie strips are a new conservation practice that protect the soil and water, while providing a habitat for wildlife. Strategically weaving a little bit of prairie back into the agriculture landscape can increase water and soil quality, habitat for wildlife and pollinators, as well as opportunities for biomass production.

February 14, 2020