Corteva Agriscience™ Agriculture Division of DowDuPont, understands the general public may have questions about vegetation management and its potential impact on pollinators. We also recognize it can be difficult to answer questions if you are approached unexpectedly. To help you manage these inquiries we have compiled a frequently asked questions handout you can provide to inquiring citizens.
Below are some key messages to try to convey if you are ever approached by concerned citizens:
- Benefits of vegetation management. Vegetation management is critical and necessary to control unwanted vegetation that may create a safety, health, occupational or environmental hazard. The safest and most cost-effective long-term solution for controlling vegetation is an integrated vegetation management program that uses both mechanical and herbicide control strategies.
- Herbicide application. Selective application of herbicides allows desirable species to flourish, increasing biodiversity. Furthermore, it is less disruptive to the landscape and controls the entire plant, so crews only need to visit the site once every two to four years.
- Product you are applying. Herbicides used by vegetation managers should not be confused with insecticides. While insecticides target the nervous system of an insect, herbicides target a specific pathway in plants. These target sites do not exist in pollinators, including bees.
- Herbicide regulation in Canada. All pesticides undergo a risk assessment by Health Canada’s Pest Management Regulatory Agency (PMRA) to determine potential toxicity to bees. Each product is assessed for both oral and contact toxicity.
Health Canada’s PMRA conducts a science-based risk assessment on herbicides, using a measurement to determine the dose that harms 50 percent of the treated test bees. The measurement is described as “Lethal Dose 50” or “LD50.” To calculate the LD50, scientists conduct an experiment that consists of feeding or directly spraying bees with different concentrations of pesticide.
The LD50 for ClearView™ herbicide is 100 μg/bee, which is equivalent to applying 112 kilograms of active ingredient per hectare1, which is around 1,000 times higher than the ClearView application rate used to control weeds. An LD50 value that is equal to or greater than 11 μg/bee is considered “practically non-toxic,” and is the safest possible category as classified by the PMRA.
Here are some steps you can take as an applicator to minimize potential pollinator exposure:
- Read and follow label directions. This minimizes error, maximizes environmental protection, and ensures compliance with laws and regulations.
- Use selective herbicides. Selective herbicides are formulated to control specific weeds or groups of weeds, reducing damage to nontarget plants.
- Conduct inventories. An inventory of existing vegetation can identify emerging noxious and invasive weed issues. Early action can control outbreaks of problem plants before they spread.
- Adjust application timing. To help reduce exposure to foraging bees, applications should be made when bees are not actively foraging (typically from mid-morning to mid-day). Bees are also less active at cooler temperatures.
- Avoid application when weather conditions increase drift. Apply products when wind speeds are low.
1 Atkins, EL; Kellum, D; Atkins, KW. 1981. Reducing Pesticide Hazards to Honey Bees: Mortality Prediction Techniques and Integrated Management Techniques.
University of California, Division of Agricultural Sciences, Leaflet 2883. 22 pp.
Corteva Agriscience is here to support you with science-based solutions. Please download our FAQ brochure from ivm.corteva.ca (under the Tools and Resources section) and provide it to concerned citizens or customers.
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