It is not fully understood how systemic insecticides travel from the area of treatment to nectar and pollen in plants. It is also unknown how long insecticidal residues remain in plants and at what concentrations. The Horticultural Research Institute started research to answer those questions and created the Best Management Practices (BMPs) for Bee Health in the Horticulture Industry based on current knowledge. This guide seeks to educate and empower the green industry on how to keep bee pollinators safe from systemic insecticides. BMPs for greenhouses and nurseries are included as well as for managed landscapes. The article proposes that when it comes to deciding whether or not to treat with a potentially hazardous insecticide, a cost-benefit analysis should be done.
Everything we do has an impact on something else, and nothing is absolute. When it comes to deciding whether or not to treat a plant with an insecticide that may be hazardous to managed honey bees or other bee pollinators, a cost-benefit analysis should be considered. If the pest management concern is great enough, even bee pollinator attractive plants may need to be treated with a hazardous insecticide. The potential of exposure should be considered. A good example is emerald ash borer (EAB). Ash trees are wind pollinated, yet bees are known to collect pollen from ash if other pollen sources are scarce. However, certain invasive pests, such as EAB, must be treated, or ash trees will die. A common EAB treatment includes neonicotinoid insecticides. Certain insecticides, neonicotinoids in particular, have great value in preventing the introduction and further spread of invasive species to gardens and landscapes. Neonicotinoid insecticides have many benefits, including broad spectrum control and a positive worker safety profile. In some instances, a neonicotinoid is the product of choice for insect pest control. If one is used (or other insecticides for that matter), steps can be taken to better ensure bee pollinator safety.