GUEST AUTHOR: Adam Pauley | Intern | National Farmers Union
This piece previous appeared in a series of posts on the NFU blog here, here, and here. It appears here under an agreement with the NFU.
Integrated Pest Management
According to the U.S. Department of Agriculture (USDA) Natural Resources Conservation Services (NRCS), Integrated Pest Management (IPM) is a sustainable, ecosystem-based strategy to manage pests. This is achieved by implementing a combination of pest prevention, avoidance, monitoring, and suppression techniques such as chemical control, biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.
Lady Bugs are sold commercially for biological control of aphids. | Wikicommons
According to the U.S. Environmental Protection Agency (EPA), there are two main principles of integrated pest management system: focusing on prevention and using pesticides only when needed. They recommend first identifying pests and determining the best preventive and control measures. This could include installing pest barriers, maintaining diverse plant communities, or introducing natural enemies of pests.
In addition to decreasing yield volatility while also reducing unnecessary use of pesticides, IPM offers numerous other benefits. By cutting pesticide use, it can improve soil and water quality. At the same time, IPM can save farmers money. Fewer pesticides often means lower input costs, and IPM can stabilize future yields and income streams.
Crop Rotation and Pest Management
According to the U.S. Department of Agriculture (USDA) report Climate Change and Agriculture in the United States: Effects and Adaptation, temperatures in the next 40 years are expected to rise 1-2 degrees Celsius. This will increase pest pressure because insects that are frost sensitive will be able to survive milder winters. An article published in Nature Climate Change indicates that climate change is widening the niche for invasive species by setting the environmental conditions under which pests invade. In other terms, climate change is offering an opportunity for pests and weeds to appear faster, in higher quantities, and over an larger area. Pests and weeds interfere with yields, and repetitive planting of the same crop can lead to yield volatility which can jeopardize food security. Further, some common means of addressing changing or increasing pest and weed pressure can exacerbate other environmental concerns, like chemical runoff into streams.
One way farmers can cope with changing weed and pest pressures is by lengthening their crop rotations. Crop rotation refers to the practice of cycling different crops on a given piece of land as a way to increase biodiversity and promote soil health. An extended crop rotation includes more crop variety than an average rotation of crops. This practice is beneficial because it prevents the proliferation of pests encouraged by repeated plantings. As an example, alternating between alfalfa and corn starves corn-eating pests, allowing the producer to protect yields and mitigate the damage that a pest that has propagated through multiple planting cycles.
Crop rotation offers other benefits as well. According to the USDA Natural Resources Conservation Service (NRCS), crop rotation decreases the amount of inputs needed, potentially increasing profit by decreasing the variable cost of production. It also increases soil organic matter and protects water quality by preventing excess nutrients and chemicals from entering the water supply.
While the soil health benefits of extended crop rotations can help mitigate climate change, this strategy also has significant value for producers whom are trying to adapt to changing pest and weed pressure and can help farmers stay productive as climate change becomes more severe.
Intercropping and Pest Management
Farmers are implementing new practices to compete with more aggressive pests, but many of the common means of doing so can exacerbate other environmental concerns, like chemical runoff into neighboring bodies of water.
Systems of strip intercropping which include corn, soy beans and other crops are advocated by researchers at Oregon State University as part of the solution to improved farming systems for much of the Midwestern U.S. | Oregon State University
One solution to both of these problems is intercropping. According to U.S. Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS), intercropping is the practice of growing two or more crops in close proximity to one another during part or all of their life cycles. While monocropping, the practice of only growing one crop variety year after year, leaves producers more vulnerable to pests that target a specific plant variety, intercropping, by providing additional plant varieties, can help slow the proliferation of pests and protect yields.
Intercropping can also be used to manage pests in more specific ways. One example of this is trap crops. According to University of Tennessee’s Institute of Agriculture, a trap crop is meant to attract pests, keeping them away from the main crop. Farmers using this method could decide to apply pesticides just to the trap crop rather than their entire field, cutting down on input costs.
In addition to managing pests, intercropping provides a number of ecological benefits. It promotes interactions between crops and pollinators, thus supporting biodiversity and wildlife species. Intercropping can also improve soil and water quality by reducing pesticide use, increasing vegetative cover, and diversifying root structure.
