Hear it from Dr. Andrew Hammermeister, the Director of the Organic Agriculture Centre of Canada (OACC) and Associate Professor in the Faculty of Agriculture at Dalhousie University, Nova Scotia, Canada.
The concept of organic agriculture has been around for nearly 100 years. In principle, organic agriculture was intended to displace degenerative practices that risked damaging the soil, the surrounding agroecosystem, and health of farmers and consumers. Organic agriculture was intended to work within the limits of natural ecosystems while supporting a diversity of plants, insects and microorganisms.
Biodiversity is very important in nature. Plant species have differences in the time of year that they grow, the type and depth of their rooting system, the kind of climate and soils they require, and their resistance to stresses from pests or climate extremes. This diversity provides cover continuously throughout the growing season, minimizing losses of nutrients, protecting the soil from erosion, and providing habitat for other organisms.
The term “resiliency” refers to the ability of an individual or ecosystem to maintain a certain level of performance after it has undergone a stress. An example would be the ability of a plant to recover after a period of drought. The ability of an ecosystem to bounce back after a stress or disturbance is critical for maintaining stability or continuity of services that the ecosystem provide including provision of food, clean water, nutrient retention, and soil protection.
MSc Student Jade Muileboom (photo source) is studying how Fusarium head blight in wheat (top) could be controlled by microorganisms living right within the wheat head. This research is under the supervision of Dr. Manish Raizada at the University of Guelph and is part of the Organic Science Cluster.
Land will eventually lose resiliency if degenerative practices are used. Here are a few examples. Leaving the soil bare with intensive tillage destroys soil structure and depletes organic matter (i.e. carbon sources) in the soil resulting in increased risk of erosion and degradation of the soil which is the foundation of our food supply while also releasing CO2 to the atmosphere. Repeated and inappropriate use of pesticides can affect non-target organisms, contaminate water supplies and result in pests building resistance to the pesticide.
Monoculture, which describes continuously planting the same single crop year after year, can deplete soil nutrients and increase risk of pest pressure as the crop is continuously favouring certain pests. Excessive or untimely application of nutrients to maximize yield can result in nutrient leaching or runoff into water systems. Essentially, biodiversity loss, increased pest pressure, declining productivity, and contamination of water systems are indicators that farming practices have exceeded ecological limits.
Organic Science Cluster researchers are studying how to strategically use plants to attract pests away from crop while also providing habitat for natural enemies of those pests. (Photo by A. Hammermeister)
Organic farmers have long been at the forefront of adopting practices that work within natural limits of the ecosystem and are regenerative. They adopt crop sequences, also known as crop rotations, that are strategically grown in a sequence that maintains good productivity and income while also maintaining soil fertility and protecting soil health. Having a diversity of crops in the rotation helps prevent pest populations from building while also supporting a more diverse community of healthy soil organisms that cycle nutrients and reduce pest pressure. Organic farmers avoid using nitrogen fertilizers manufactured using fossil fuels; instead they recycle nutrients by using manure and compost, or they use leguminous plants to capture nitrogen from the air with the help of Rhizobium bacteria. Growing plants to capture and cycle nutrients not only supports crops but also supports healthy soil biology. These soil building practices offset the impacts of tillage to maintain health and productive soils. Organic farmers avoid pest pressure through crop diversity, resist pest pressure by selecting resistant cultivars of crops, and compete with pests by having healthy soil biology belowground and competitive plant populations above ground. By adopting these regenerative practices, organic farms are internationally recognized for supporting higher biodiversity than non-organic farms.
Despite using these regenerative practices, organic farmers continue to seek improved tools and practices that address production challenges while enhancing productivity and sustainability. The toolbox for organic farmers is limited since they must follow production standards and a list of approved inputs that are regulated by the federal government; they cannot address problems with synthetically manufactured fertilizers, pesticides or genetic modification. This means that researchers must find solutions that are both innovative and ecological in order to support organic farmers. Ecological innovation involves understanding how different parts of the ecosystem work together to be resilient and efficient in using water, light and nutrients, and then developing tools and practices that optimize the ecosystem to produce crops and livestock. The key here is that the solutions that are within ecological limits while reducing need for inputs.
Dr. Martin Entz at the University of Manitoba shows how thick mulch created by no-till crimping of a hairy vetch green manure can suppress weeds while also providing nitrogen to this flax crop. (Photo by A. Hammermeister)
The national Organic Science Cluster program includes a wide range of projects that support ecological innovation ranging from regenerating soil health by storing carbon and maintaining healthly soil biology, identifying biological controls of insect pests and diseases to reduce use of pesticides, providing year-round fresh vegetables through organic greenhouse production, and displacement of nitrogen fertilizer manufactured with fossil fuels.
Masters student Jade Muileboom (supervised by Dr. Manish Raizada at the University of Guelph) is studying how to control Fusarium head blight, an important disease of wheat, by identifying microorganisms within the wheat head that can suppress or even displace the disease. Dr. Juli Carrillo at the University of British Columbia is leading a team of researchers to develop a series of ecological practices to control spotted wing drosophila, an important pest of small fruit crops. Her team is studying a combination of strategies for maintaining natural enemies, developing biological controls, and using bio-products to promote plant resistance and deter the pest.
Drs. Martin Entz at the University of Manitoba and Derek Lynch at Dalhousie University (as well as several other researchers) have been studying novel approaches to managing legumes, like clover or vetch, as green manures to capture nitrogen from the atmosphere instead of using nitrogen fertilizers. The largest sources of fossil fuel energy use in non-organic agriculture is the manufacture of nitrogen fertilizers. Drs. Entz and Lynch have been studying novel techniques to manage these green manures without tillage while regenerating soil health, capturing carbon in the soil, and supporting a diversity of organisms above- and belowground.
In summary, organic has been around for a long while now. Organic producers and researchers studying organic are taking an alternate pathway toward sustainability. They are developing innovative tools and practices that regenerate soil health, biodiversity, and water quality through a deeper understanding of both the limits and possibilities of the natural ecosystem.
About the Author:
Dr. Andrew Hammermeister is the Director of the Organic Agriculture Centre of Canada (OACC) and Associate Professor in the Faculty of Agriculture at Dalhousie University, Nova Scotia, Canada. Andrew has worked with the OACC since 2002, collaborating in research on grain, vegetable and fruit cropping systems, exploring soil fertility and weed management. Andrew is the Science Director for the Organic Science Cluster, the coordinated national initiative for organic agricultural research in Canada where he leads national organic research priority setting, coordination, and impact assessment. He sits on the national organic standards review committee and several other organic sector committees.
Learn more about Organic Agriculture Centre of Canada here.
