Jeff Mitchell increases student awareness of the importance of soil health at the Reedley College 2015 STEM Conference.

(The following was taken from Jeff Mitchell's presentation.)

Jeff Mitchell, Cooperative Extension cropping systems specialist at the UC ANR Kearney Agricultural Research & Extension Center and in the Department of Plant Sciences at UC Davis specializing in vegetable cropping systems, irrigation management, soil quality, organic soil amendments, extension models, and postharvest physiology was a presenter at the 2015 STEM conference held at Reedley College on April 25, 2015. About 1300 middle and high school students from the local region came to learn about careers requiring an educational focus on science, technology, engineering, and/or math. Mitchell's workshop was called “SOIL: Get Your Hands Dirty!”

Mitchell shared how he became an extension specialist, emphasizing that broad life experiences can often help you discover your passion and lead to satisfying career choices.

Students learned that we will have an additional 3 billion people by 2050. This leads to the problem that the estimated food production demand from 2010 through 2050 will be 730 Exacal (an Exacal is 10¹⁸ calories), which is more than the demand we had over all of human history. Related problems are that we risk having a food production deficit and a water deficit. There is a linear relationship between soil organic matter (%) and available water content (%).  So, if we need to increase our food production with finite resources, we need to keep our soil healthy and productive. Whichever country develops strategies and technologies that allow the soil health and soil water availability at the root zone to be maximized will be ahead in the race to feed the world.

Just like caring about our own health, we must care about the health of our natural resources. Mitchell shared that 2015 is the international year of soils with the motto, “healthy soils for a healthy life.” Innovative farmers and scientists are using the concept of soil health, which “has added principles and dimensions of soil biology and agroecology to our understanding and consideration of the overall health of the soil resource base. It is not easy to perfect a no-till or conservation agriculture tillage strategy, but once one succeeds, the soil health approach allows a farmer to “maximize profits and increase production while protecting [his or her] land.”

Students were posed the question, “Are there indications that soil function, soil quality, or soil health is declining in California?” This question can be answered by testable hypotheses, and is a good place for university/federal research support partnerships. “Is there evidence that water intake characteristics of soils might be improved? Is there evidence that the value of soil biodiversity may not be expressed or realized to some sort of optimal extent?... Is there evidence that soil water storage and movement are not what they might be for optimal water use efficiency and benefit?”

Mitchell noted that Dr. Dwayne Beck of the Dakota Lakes Research Farm commented that natural systems…

• Harvest the maximum amount of sunlight
• Leak very few nutrients, including CO₂
• Have diversity
• Tend not to export nutrients
• Make maximum use of water and nutrients by having highly developed porosity and Mycorrhizae (VAM) webs
• Do not do tillage

Mitchell also noted that USDA NRCS states that managing for soil health includes…

• Minimizing soil disturbance
• Maximizing the diversity of plants in rotation/cover crops
• Keeping living roots in the soil as much as possible, and
• Keeping the soil covered with plants and plant residues at all times

… and will unlock the secrets of the soil.

Mitchell noted that there are many farmers, university scientists and USDA scientists studying conservation agriculture as a tool to meet the challenges of population growth. Conservation Agriculture

• Has developed to be a technically viable, sustainable, and economic alternative to current crop production practices
• Is gaining acceptance in many parts of the world as an alternative to both conventional agriculture and organic agriculture
• Is the integration of ecological management with modern, scientific, agricultural production
• Is not ‘business as usual,' based primarily or solely on maximizing yields
• It is based on optimizing yields and profits to achieve a balance of agricultural, economic and environmental benefits
• It advocates that the combined economic and social benefits gained from combining production and protecting the environment, including reduced input and labor costs, are greater than those from production alone.

Conservation agriculture strategies include

• Minimal soil disturbance
• Preservation of residues that provide permanent soil cover
• Diverse crop rotations
• Use of cover crops
• Integrated pest management
• Reliance on precision, highly efficient irrigation
• Controlled or limited mechanical traffic over agricultural soils

Mitchell noted that “More with less”…agriculture in the future will have to sustainably produce more food, feed, fiber and energy on less land through more efficient use of natural resources and with minimal impact on the environment in order to meet growing population demands. This will become a global imperative. In 2012, Beck stated that the USDA Agricultural Research Service National Program 216, Agricultural Systems Competitiveness and Sustainability is “The agronomic and ecological equivalent of the moon race of the 1960's…They did not achieve a successful landing by testing small incremental improvements in rocket design. They did it by having a specific goal and teams focused on developing the techniques required to achieve that goal.”

Therefore, if a student's passion is to benefit the world by ensuring that there is a sustainable, safe, affordable and abundant supply of nutritious food, feed, fiber, housing and water, then a career pathway in agricultural engineering, biological engineering, agronomy, soil science, plant science, genetics, entomology, nematology, plant pathology, agricultural economy, and other related STEM fields of study are all good choices.

Students were able to see the benefits of an ongoing conservation tillage trial that is being conducted at West Side Research & Extension Center. There were samples of conventional and conservation tillage soil. Students noted that the conservation tillage soil was able to hold its shape while soaking up water when dipped in the water, and that the conventional tillage soil dispersed into the water.

Jeff Mitchell teaching students about the importance of soil productivity and conservation agriculture strategies.

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