In 2014, a Harvard study found that low levels of insecticides called neonicotinoids contributed to colony collapse disorder and were killing bees. Neonicotinoids are a relatively new class of insecticides that share a common mode of action that affect the central nervous system of insects, resulting in paralysis and death. They include imidacloprid, acetamiprid, clothianidin, dinotefuran, nithiazine, thiacloprid and thiamethoxam.
Recently, one of the largest field studies in Hungary and Britain found that exposure to neonicotinoids weaken bee colonies. Fields planted with canola were treated with insecticide. Nearby beehives fared worse through the winter, compared with those near untreated crops.
How can you help? Look for the STB Verified Safe For Bees label on your gardening products. Or ask your favorite brand to get listed here.