Organic Specialty Crop Production and Pest Management Basics
By Dr. Ayanava Majumdar, Extension Entomologist and SARE Program Coordinator at Alabama Extension, Auburn University
Organic farming, as part of sustainable agriculture system, emphasizes profitable farming, good stewardship of natural resources (land/air/water), and high quality of life for everyone involved from production to consumption. Today, organic food is one of the fastest growing agricultural sector today and there is plenty of information about this on the Internet. In fact, organic food demand is currently outpacing availability of organic crops—so we need more farmers! This article should appeal to experienced growers as an overview of sustainable agriculture systems approach and benefit new farmers with some ‘immediately useful’ information. As a researcher in the area of sustainable agriculture, we have gained much scientific advancement in the past 10 years with applied research directly benefiting producers through the proliferation of electronic media and communication technologies.
Components of a sustainable agriculture system: There are some great models for defining how sustainable agriculture systems work, and one of them is provided by the United Nations Sustainable Development Solutions Network (UN-SDSN). Sustainable agriculture production systems in general are affected by three basic yield-defining factors, namely, varietal characteristics (agronomic principles), environmental conditions (climate), and management approaches (farm-specific activities). Organic producers have to carefully plan for each factor and optimize their practices for maximizing crop production. The varietal characteristics include sub-factors such as plant physiology, growth vigor, yield potential, fertilization etc. Environmental conditions play a major role today as we experience climate change as a major phenomenon. Producers have to take into account levels of solar radiation, day length, water availability to crops to plan crop rotations, variety selection, and harvest. Management approaches for organic farmers include farm-planning activities, crop cycles, soil health conditions, water and pest management methods for short-term and long-term benefits. Interestingly, as organic growers get more experienced in farming (beyond the transition phase), the emphasis of sustainability shifts from basic agronomy and production to intensive management of crops to stop yield reduction. Just think about the variety of disease, insect, and weeds that are called the yield-reducing factors. The hot and humid growing conditions of the South are perfect for year-round pest activity; this calls for a unique organic approach to organic farming that may be different with productions systems from other parts of the country.
Basic approaches to organic pest management: Before I forget, let me encourage all beginning farmers (and anyone wanting more information on organic IPM) to attend the upcoming workshop session at the 2020 SSAWG Annual Conference in Little Rock, AR. There are three basic levels to organic pest management which really starts after proper identification of the pest issue. Use a certified crop adviser, pest specialist, or any resource you may have to get disease/weed/insect identified. Misidentification of pest and overspraying are two most common problems on organic small farms that have real economic consequences (factor in your labor along with cost of approved materials and application equipment). The first level of pest management is called ‘systems based practices’ that include all basic farming activities such as crop variety selection, irrigation, rotation, soil fertility/health etc. Field sanitation (removal of crop debris to reduce carry-over of disease/insects) and trap crops (deterring pests by using highly attractive sacrificial plants in a limited area) are some unique approaches to insect pest and disease reduction. Look up trap crop videos for leaffooted bugs, squash bugs, and yellowmargined leaf beetles on YouTube to learn more. Using cover crops and reduced tillage is good for long-term weed suppression and for the environment.
Recently, there is renewed interest in pest exclusion systems for temporary or permanent systems. Use of mechanical means is the second level of organic pest management and can be very beneficial when the plants are small and vulnerable to insect pests. Low-cost insect exclusion fabric such as Super Light Insect Barrier or AgroFabric Pro are different from traditional row covers making them suitable in the hot weather in the Deep South. In Alabama, we have 11 on-farm demonstrations of using 50 percent shade cloth around high tunnels as a permanent high tunnel pest exclusion or HTPE system (check out the HTPE video on YouTube!). Always consult someone with knowledge or experience in these exclusion system before adopting them at the farm level as there can be unwanted side effects.
Biopesticides are the most popular means of pest management in organic systems due to their specificity and low environmental harm when used judiciously. There are four major categories of bioinsecticides based on their primary mode of action, namely, physical dessicants, contact action, stomach action, and volatile products that mask plant smell. The top five organic products popular among growers include Bt-based insecticides, pyrethrin, spinosad, neem, and insecticidal soap. In recent years, we have seen the development of premix insecticides that have two insecticides (e.g., Botanigard Maxx) or an insecticide + disease control (Leap). Numerous studies have been done on pesticide rotations to avoid resistance issues and conserve natural enemies. Trap cropping mentioned earlier is a great way to conserve NEs and enhance biodiversity on small farms.
The bottom line for farmers is the economic benefit from sustainable farming systems. Based on my experience in Alabama and the Southeast, proper planning in crop production, harvesting and marketing are absolute essential elements for profitable farming. Based on grower surveys and research data, we now know that a proper IPM plan can reduce crop losses 30 to 50 percent at harvest. Applied crop and IPM research will continue to provide benefits to the producers who are excited to grow local fresh foods for the customers that want it.
Dr. Ayanava Majumdar is an Extension Entomologist and SARE Program Coordinator at Alabama Extension, Auburn University, USA. He conducts research on a variety of specialty crops and coordinates grower training through the Alabama Beginning Farmer program (www.alabamabeginningfarmer.com). Download the Farming Basics app or enroll in the free online course for more assistance.