Optimizing Agricultural Use of Diverse Soil Landscapes: Small Organic Vegetable Farms in the Driftless Area

View the project report

Commodities

• Vegetables: artichokes, asparagus, brussel sprouts, cabbages, carrots, cauliflower, celery, greens (leafy), greens (lettuces), parsnips, sweet corn, tomatoes

Practices

• Crop Production: organic vegetable production
• Natural Resources/Environment: soil heterogeniety and erosion
• Production Systems: organic agriculture
• Soil Management: organic matter, soil analysis, soil quality/health

Problem:

The Driftless Area covers 24,000 square miles at the junction of four North Central States: Minnesota, Wisconsin, Iowa, and Illinois. The name indicates that the region, in comparison to the surrounding areas, lacks glacial deposits. Even though the region's glacial history is more complex, the name captures the region's strong physiographic identity. Its complex topography does not allow mechanized industrial farming, which is overwhelmingly present in the North Central states. 

Farmers contributing to this proposal were eager to list topography-affected soil problems: (i) extremely diverse soil texture, moisture, and organic matter contents that limit timely field preparation, adopting ideal rotation, and fertilizer application, (ii) flooding and saturation of low-lying fields, (iii) distinct micro-climate between the ridge tops and valleys, and (iv) rapid soil erosion across the range of slopes (see collaboration letters). As the farmers’ responses highlight, it is within the individual farms that the highly variable soil conditions occur in this unique region. However, most research on soils and soil erosion focus on watershed scales. Consequently, we lack a practical guideline for  small-scale farmers to optimize the sustainability and productivity of their lands according to their complex soils and topography. This issue is urgent as the Driftless Area is often seen as a magnet for small-scale farmers.

Approach:

This research project will:

1. Collaborate with at least six organic vegetable farms in the Driftless Area, as organic vegetable production is one of the most common agricultural land-uses in the region. Via focus group and individual farmer interviews, we will learn how soil-topographical relationships are factored into the land-use decisions the farmers make.
2. Characterize how topography affects land uses, vegetable productivity, and soil health within individual farms owned by our collaborator farmers. We will collect soil properties data and use remote sensing and high-resolution elevation data. Remote sensing-based characterization of vegetable health and yield will be made as a function of topography.
3. Integrate farmer narratives and biophysical data in order to (1) document novel economic and environmental effectiveness of within-farm farmer soil-landscape use and (2) co-develop alternative models for agricultural use of complex soil-landscapes in part by applying precision agriculture principles and technologies in organic agriculture.

Relevance: All soil parameters and the agricultural impacts on soil erosion and hydrology strongly reflect topography that varies within the scales of small farms in the Driftless Area. Assessing and improving these connections are important for organic farm productivity and sustainability.

Our objectives are to: (1) better understand within-farm agricultural use of soil landscapes, and (2) to support positive land-use decisions, or propose improved or alternative within-farm agricultural use of soil landscapes and management practices by combining precision agriculture and organic agriculture.

Our expected outcomes are (1) farmers have increased knowledge and awareness about the role of topography on the productivity and sustainability in their farms and (b) farmers have plans to change or do something differently based on our research disseminated through our outreach.