Over the last few years, the amount of space occupied by bees in the French public debate together with the well-known benefits of the products of their hive has attracted the interest of social scientists. Indeed, bees have become a symbol of the biodiversity crisis. Social scientists, like us, are sometimes invited to join multidisciplinary projects run by biologists specializing in bees. The aim of such involvement is to help the biologists to convince professional beekeepers to make their practices greener, notably with respect to their handling of the Varroa mite. However, the beekeepers we studied in the south of France are not keen to give up their conventional practices. Based on chemical products, these are efficient, simple, and cheap as opposed to environmentally friendly, chemical-free techniques (scraping or removal of the brood), which are seen to be riskier and more complicated to implement. This article describes and analyzes these obstacles and the relationship to scientific and nonscientific knowledge they reveal.