How are Pesticides-Insecticides-Herbicides Harmful to Pollinators?
Systemic Pesticides
Both systemic and non-systemic insecticides can be lethal to pollinators. Unlike contact pesticides, which remain on the surface of the treated parts of plants (e.g. leaves), systemic pesticides are taken up by the plant and transported throughout the plant (leaves, flowers, roots and stems, as well as pollen and nectar). Systemic insecticides are intended to kill via ingestion of plant tissue contaminated from the inside over time, while non-systemics are designed to kill via contact with or ingestion of surface residues shortly after application.
Particularly problematic to pollinators and other beneficial insects are systemic pesticides know as Neonicotinoids (Neonics). These are extremely toxic and are very persistent; the chemicals are consumed not just by pests but also by bees, larval (juvenile) and adult butterflies, and the many beneficial predators and parasitoids that eat pollen or nectar as adults.
Neonics affect the central nervous system of insects, leading to eventual paralysis and death. Many systemic insecticides are toxic enough to kill adult or larval (juvenile) honey bees, bumble bees, and/or solitary bees at very low concentrations. In addition, researchers have documented effects including impaired reproductive capacity, flight, navigation, learning, immune response,
5 common Neonics on the market: clothianidin, imidacloprid, thiamethoxam, acetamiprid and thiacloprid; the former three being a specific risk to bees.
Systemic Pesticides: A Reference and Overview
Searchable Systemic Insecticide List
8 Pesticide Myths Every Gardener Should Know (Bee City USA Blog Post)
What About Organic Pesticides?
Habitat Planning for Beneficial Insects (A Guide to Planting for Biological Pest Control: Attracting Predatory Insects to Assist)
