Solarization or Occultation? Optimizing Tarping for Soil Health and Productivity in No-Till Vegetable Production

View the project final report

Commodities

Practices

• Crop Production: no-till
• Soil Management: soil microbiology, soil quality/health

This SARE Farmer Grant project proposal seeks funding to investigate the effects of different tarping techniques on soil health and the soil ecosystem. Solarization and occultation have provided a means of effective cover crop termination when paired with roller crimping, which has enabled no-till production at Cedar Circle Farm where we are in the process of transitioning to a no-till management system. This project seeks to examine these strategies for their effects on the soil health and produce information that we can use to maximize the rehabilitation of the soils at Cedar Circle Farm. In measuring the residual effect of these tarps on soil respiration and available nitrogen throughout the growing season we can begin to understand better the total effect they have on the soil ecosystem, and how energy and nutrients are cycling through it. With this information we can choose a strategy that maximizes soil health. We hope to build this knowledge into our educational programs regarding our no-till management system that we give to other farmers in the area and into our participation in winter workshops and conferences. Ultimately this project seeks to produce the information necessary regarding a crucial step in the Cover Crop-Based, Tarped, No-Till Management System (CCTNT) for farmers to fully evaluate the costs, benefits, and risks of making a transition to no-till and to hopefully advance the case that this management system can be both environmentally responsible and economically profitable. 

The purpose of this investigation is to determine whether there is a difference in the effect on the soil microbiology between solarization and occultation, particularly in their application for the termination of a cover crop within a no-till system, and to characterize this difference over a growing season. Specifically this project will undertake the following tasks:

1. Examine the effect of different tarping strategies on soil respiration and plant available nitrogen levels.
2. Characterize this effect from the removal date of the tarps through the end of the growing season 

These objectives will give us information on the health of the soil ecosystem and soil fertility, so that we can contextualize the soil health aspects of tarping in this application within a wider discussion of the potential costs and benefits of the Cover Crop Based No-till Management System (CCTNT) to be used in our outreach regarding this novel management system.