AgNet DEMO

Category: Pollinators

  • Getting Bugs to Work for You: Biodiversity in Action

    Bees, flies and spiders are all attracted to floral resources and provide predation and pollination services in crop production.

    By Jason Schmidt, Carmen Blubaugh and William Snyder

    Before large monoculture agriculture became commonplace, farms had a bit of everything — from a vegetable garden and a fruit orchard, to a chicken coop and a honeybee hive, to a natural forest and even a lake or creek. These farms had rich and vibrant plant and animal life, healthy soils and good yields.

    In the last 80 years or so, farms have become larger, more uniform in crops, with higher inputs of water, fertilizer and pesticides — all to be able to get high-quality yields, feed a growing population and remain profitable. But another change is happening: our awareness that we need to restore some of that diverse farm life to sustain production.

    Biological diversity or biodiversity, the diversity of living things, has gained attention in the last decades due to the great value of many ecosystem services (i.e., natural ecosystem components that benefit humans) such as pollination and natural pest control. Building diverse, healthy and sustainable food production requires more than knowledge of pesticides, nutrients, irrigation and plant germplasm.

    Current messaging emphasizes “Protecting the life that sustains us” (the mission of the Xerces Society), and large global research teams are mobilized to evaluate the importance of biodiversity for crop production. A biodiversity-based economy places greater worth on biodiversity than just direct products. Conservation and restoration of landscapes is gathering interest as methods to provision biodiversity and associated ecosystem services.

    Could a field full of insects ever be a good thing? Maybe, if you are into “biodiversity-friendly” farming. For each pest, there are likely 1,000 species that are either beneficial or have an unknown role in agriculture. For the most part, having a field full of insects could be a good thing when there are many different types of insects. This is especially good if we see lots of bees, butterflies and predators, and a lot fewer pests damaging plants. Sadly, it is more common to hear about the bad bugs, especially when one species is having a tremendous impact on production.

    Generally though, more species provide more functions for a system. With diverse communities, there are many workers to do the necessary tasks (i.e., nutrient cycling, pollination, pest control, etc.) in the system. Having multiple species doing the same type of work can provide a back-up in case a player in the starting lineup goes down and a sub is needed. This is called resistance or ecological resistance.

    Planting wildflower strips along the edge of fields in marginal habitat not suitable for production can support diversity.

    Building diverse systems with many different species boosts resistance in the farming system because there is less risk to lose key functions like pollination and pest control. For example, growers are currently relying very heavily on one species of pollinator, the honey bee, to do a lot of work. Now that the honey bee is facing new parasites and other challenges, pollination is at risk.

    Another attribute of diverse systems is resilience. When things do go wrong or conditions change, diverse systems commonly bounce back quicker. Let’s looks at the steps growers can take to help restore and maintain biodiversity.

    STEP 1

    Plan for biodiversity during land conversion. Research has revealed that loss of diverse lands is likely one of the big drivers of biodiversity loss. We can tell this by using land cover maps to understand large patterns of habitat change. One clear pattern is that most (if not all) of the high-quality arable land is already in use, and in some areas, there is not much undeveloped land left to expand or we will be farming in wetlands, lakes, rivers or deserts.

    Habitat loss has become a strain on biodiversity because plant and animal species simply do not have places to live. Land-use analysis tells us that planning of any new land for conversion should also plan for providing permanent, non-cropping areas for buffering between waterways and other fields. These areas can be wetlands, stream edges, etc. The current rule of thumb, which requires a lot more study, is that 20% of land should be in non-cropping areas such as native forests and diverse wildflowers to buffer areas and provide food and shelter for biodiversity to prosper.

    STEP 2

    Grow fields with off-season cover crops to provide resources for aboveground and belowground diversity.During winter, when crop vegetation is dormant, habitat may be lacking in very large stretches of farmland. This means that valuable pollinators, parasitoids and predators have nowhere to dwell so they must rebuild their populations from scratch every year. Growing more green material builds a healthy insect and microbial community (which breaks down organic matter, brings nitrogen into the soil and improves soil structure). However, a soil left bare rapidly breaks down last season’s plant roots and releases carbon to the atmosphere instead of storing carbon and nitrogen for the next season. This results in a loss of valuable components of the nutrient cycle.

    Cover crops and mixed plantings can diversify production.

    The good news is that there are some simple, cost-effective ways to retain and build biodiversity aboveground and belowground. Cover crops (either single or mixed species) bring nitrogen and carbon into the soil and hold soil in place to reduce nutrient loss and erosion. They also provide habitat and food for species during times when the major crops are not growing in the field. Cover crops are an inexpensive solution to building soil organic matter, soil structure, and to feeding the invisible biodiversity of microbial (fungi, bacteria and algae) life.

    Researchers are just beginning to understand the complexity and dependency of the soil microbial community on cropping systems. Microbial life is incredibly diverse and very small. Biodiversity in soils can reduce vulnerability to extreme weather and to insect and pathogen attack by boosting plant defenses.

    Step 3

    SNAP to it! An acronym coined by Steve Wratten at Lincoln University in New Zealand is SNAP — provide shelter, nectar, alternative food and pollen. Habitat planning and restoring native habitat to agricultural landscapes can achieve SNAP conservation goals for the future of sustainable food and fiber production and help maintain valuable ecosystem services we depend on. Loss of habitat is a significant driver of biodiversity loss, so habitat management will help restore and sustain biodiversity in agricultural landscapes.

    So, what can we do? Practice integrated pest management and use pesticides only when there is evidence that they are needed (i.e., if scouting has shown the number of pests is over a harmful threshold). Practice crop rotation, diversify production with multiple crops, maintain permanent plantings of flowering plants in marginal areas of the field, and improve forest edges and buffers between agricultural land and waterways.

    Let’s SNAP our farms into rich, biodiverse lands to stimulate natural regulation of our food and fiber production ecosystems and to further agroecosystem tourism.

    Jason Schmidt is an associate professor, Carmen Blubaugh is an assistant professor, and William Snyder is a professor — all at the University of Georgia.

  • Effectively Managing Pests While Protecting Pollinators

    By Sylvia Willis, Amy Vu and Jamie Ellis

    Pollinators play an important role in the production of crops around the nation. Different crops rely on different techniques for pollination. Corn, for example, uses wind to carry pollen to female flowers, whereas watermelon depends on pollinators to deliver pollen. Pollinators include insects, birds and bats.

    Many fruits and vegetables result directly from pollinators such as honey bees. In apple, cranberry, melon, broccoli and almond production, honey bees are the most common pollinator. Honey bees are responsible for a significant portion of the world’s food production and contribute nearly $20 billion to the crop industry by providing pollination services all over the United States.

    In Florida, the hot, humid climate is ideal for crop production throughout the year, but this favorable environment also paves the way for various pests that negatively impact crops year-round. Growers use integrated pest management (IPM) to consider the risks and benefits associated with cultural, chemical, biological or physical control methods to combat pests. Typically, as a last resort, a chemical control is utilized to save a crop. When selecting a pesticide, growers should consider a chemical’s efficiency of pest control and potential impacts on pollinators when applied. 

    PESTICIDE EFFECTS
    Bee hives. UF/IFAS Photo by Tyler Jones.

    There are many factors that contribute to honey bee and pollinator stress, one being the use of insecticides. Effects of certain pesticides on bees can vary from no harm to acute harm (bee or single colony death) to chronic harm (altered bee behavior or physiology, reduced reproduction, colony decline or death). Suspected pesticide exposure is one of many biological and environmental factors associated with bee colony loss. Bees are likely exposed to pesticides outside the hive when foraging during the day. Plant foliage, pollen, nectar and soil can all contain potential toxins after direct application or drift from certain pesticides.

    Reading and properly interpreting pesticide labels and exposure warnings to honey bees and pollinators is vital. According to the Environmental Protection Agency, if a product is intended for foliar application to crops and contains a pesticide toxic to pollinators, the label must include appropriate cautions. Examples of bee and pollinator hazard warning statements are:

    • “This product is toxic to bees exposed to treatment and for more than five days following treatment.”
    • “Applications to all crops may be made at any time. Fenpyroximate is practically nontoxic to bees and wasps when used according to this label.”
    PROTECTION PRACTICES

    Protecting pollinators from pesticide exposure is on the forefront of many growers’ minds when considering pest control methods. For crops that require bees for pollination, it is in the best interest of the grower to protect bees. Without proper pollination, the grower’s crop production and yield are negatively impacted. There are a variety of best management practices that growers utilize every day to minimize impacts on honey bees and pollinators. These include:

    • Following the label – THE LABEL IS THE LAW
    • Obtaining a pesticide license to legally spray pesticides
    • Applying pesticides only when necessary
    • Employing IPM practices and using chemical control as a last resort
    • Spraying pesticides at night (label permitting) to maximize safety of honey bees and other pollinators
    • Utilizing target pesticide application such as injecting, rather than broad application
    • Selecting pesticides that require fewer applications, minimizing risk potential
    • Applying less toxic formulations and compounds
    • Developing a pest management plan that considers bee foraging during bloom
    • Understanding a crop’s pollination requirements to minimize exposure
    • Planting beneficial plants along field edges to provide additional resources for honey bees and other pollinators
    • Maintaining a good relationship with beekeepers and notifying them in advance of an application
    • Consulting with fellow producers, beekeepers and Extension professionals for recommendations
    EXTENSION’S ROLE

    Through services and educational efforts offered by Extension services, growers are provided appropriate tools to combat pest issues while also protecting pollinators, the environment and human health. Extension provides educational classes to enhance grower knowledge of pollinator protection on topics such as IPM (i.e. monitoring techniques, pest and plant knowledge, and pesticide selection) and best management practices regarding pest control.

    If pesticide application is necessary, Extension provides the training, testing and necessary certifications required to apply pesticides legally. In addition, Extension highlights up-to-date pollinator protection label changes during trainings and classes. Additional efforts of Extension agents and specialists include providing updates throughout the growing season to inform producers on potential pest issues, pesticide recommendations, and notifying producers of possible impacts on pollinators of certain products. 

    Understanding the importance of pollinators on the food system has brought increased awareness for pollinator protection programs and trainings. Growers can make a difference by making informed decisions to select and utilize chemicals with pollinator protection in mind. By building positive relationships between beekeepers and growers, an open dialog of communication can be established. As a result, growers can rely on Extension services when questions on chemical safety regarding honey bees and other pollinators arise.

    See Minimizing Honey Bee Exposure to Pesticides at edis.ifas.ufl.edu/pdffiles/IN/IN102700.pdf for more information on sustainable production practices and guidance on risk-reducing strategies to protect honey bee and pollinator populations.

    Sylvia Willis is the University of Florida (UF) Institute of Food and Agricultural Sciences Extension agriculture agent in Suwannee County. Amy Vu is an Extension coordinator and Jamie Ellis is the Gahan endowed professor, both at the UF Honey Bee Research and Extension Laboratory in Gainesville.