Prairie Strips to the rescue? A new spin on a traditional conservation practice


Prairie strips aerial view ... Photo above shows an aerial view of prairie strips on the Larry Stone farm near Traer. Photo courtesy of Lynn Betts.

by Matthew Frana
Upper Iowa Watershed
Project Coordinator
Winneshiek County Soil & Water Conservation District

God’s Country…a term Iowans use to describe their state and home. Nowhere in the state is this truer than our beautiful northeast corner, where we take great pride in our county, community and environment.

As we continue to enhance this Garden of Eden for future generations, four environmental concerns are often targeted as issues to address: 1) Nutrient leaching and 2) Soil loss – Fertilizers (nitrogen) leaching from our lawns and fields are directly linked to the Gulf of Mexico “Dead Zone,” while our soils (carrying phosphorus) wash off our land at unsustainable rates, jeopardizing productivity for future farmers; 3) Flooding - We’ve seen an increase in heavy rain events with increased occurrences of flooding, contributing to more intense soil loss and costly damages to infrastructure and property; and 4) Pollinator declines - Pollinators including bees and butterflies have had population declines that have sparked national concern and are potential indicators of more serious problems down the road.

Iowa was once dominated by tallgrass prairie, which covered approximately 85% of the state. It owes its productive soils and agricultural dominance to this diverse ecosystem. Iowa’s native vegetation is a very resilient, deep rooted system that holds its soils and soaks up rain like a sponge. Since European settlement, more that 99% of the original tallgrass prairie has been converted to cropland or urban areas.

Our state’s success has been at the cost of its water quality, biologic diversity, and ability to retain water in the landscape. A new spin on a traditional practice, prairie strips, have the potential to reestablish some of Iowa’s past resilience back into the landscape. Similar to contour buffers, prairie strips instead utilize a diverse mix of native prairie species, taking advantage of their stiff stems that slow surface water and capture sediments, while deep roots allow water to infiltrate and soak up nutrients that pass through them.

Field trials conducted by Iowa State University have shown substantial improvements in addressing the four above-mentioned issues. Their studies indicate converting just 10% of a crop field to native prairie at strategic locations can reduce soil loss by 95%, reduce water run-off by 40%, while reducing 77% of phosphorus and 70% of nitrogen from overland flow of surface water. Research has also shown a three-fold increase in pollinating insect species and double the bird species in fields with prairie strips verses those without.

This increase in biodiversity can help protect crops from destructive pests like rootworm and aphids. Prairie strips are most effective when established on the contour of a hill, in locations susceptible to erosion, and the bottom of the slope. They are typically 30-50 feet in width and can be designed to fit your farming patterns and row direction. If you have a spot where you think you could use a terrace, consider prairie strips.

They are much less expensive to establish, little if any yield loss on crop acres that terrace construction would cause, and they can be moved/modified easier to adjust to future changes in equipment size and farming patterns. A tithe to our land that has provided us so much, adopting the prairie strip 10% principle provides a solution to restore some of Iowa’s natural resilience and aesthetic beauty, while remaining economically viable, improving agriculturally sustainable, and enhancing our environment for future generations.

Do you have a big yard you mow? Consider planting portions of your yard to native prairie. In addition to saving yourself time and money (mower gas and maintenance), they provide sponge-like, water retention patches across the landscape while enhancing wildlife habitat with wildflowers blooming throughout the growing season.

Want to learn more about prairie strips? A quick internet search will provide plenty of information. Also, feel free to contact your local NRCS office for assistance on designs and establishment, with potential cost-share opportunities to offset the cost of installation.

This article was reviewed by the STRIPS science team at Iowa State University for science/economic content related to prairie strips August 15, 2018.