I must comment on “The Changing Landscape of Orchard Management” feature in the recent Sustainability Issue. The article describes the severe challenges posed by aggressive alien insects to the production of marketable fruits. “Finding the balance that will keep the orchards profitable while maintaining a healthy environment” will be especially difficult if one of the listed insecticides is used. Actara is a trade name for Thiomethoxam, a neonicotinoid (neonic). Like all neonics it is highly potent in killing all kinds of insects and arthropods and it works systemically by making all parts of a plant lethally toxic. Thiomethoxam has a half-life in soil from 54 to 385 days. Significant toxic amounts persist much longer and will be incorporated into plants that become toxic. Application to orchard trees by spraying presents a great risk of collateral damage from killing beneficial insects immediately and over time. The product label gives explicit advice on “Protection of Pollinators,” including temporary removal of honeybee hives and elimination of any weed flowers in the orchard. These precautions do not protect the native pollinators that do the bulk of the pollination work. Native bees, bumblebees, wasps, flies, butterflies and moths may get killed as larvae on their respective host plants or while foraging. The result will be great reduction of biodiversity, reduced production of pollinator-dependent crops, food shortage for birds and imbalance of remaining insect populations. “Integrated Pest management” will be severely hampered. Neonics are now used widely in field agriculture with effects similar to DDT that caused Silent Spring several decades ago. Let us hope that neonic use in orchards can be avoided or – if absolutely necessary – can be limited to guarantee that no overspray or drift occurs.
Little Sturgeon, Wis.