Improved seeds varieties have led to an increase in agricultural production as well as to a change in agricultural practices and input use. While some of these new practices can be more environmentally sustainable, others may lead to a higher level of environmental degradation. In a case study using an original survey method of farming households on the Philippine island of Mindanao covering the past ten years, this paper finds a very robust positive correlation between herbicide tolerant corn cultivation and landslide occurrence. This effect is robust to the inclusion of plot fixed effect, indicating that physical characteristics of the farm do not explain the results. Instead, more aggressive weed control via broad-spectrum herbicide appears as a likely mechanism.