Weed and soil management: A balancing act *

Weed management interacts with soil in many ways. Its primary aim of reducing the number and biomass of non-crop plants means that it simplifies agroecosystems, although it produces negative ecological and environmental outcomes including reducing soil health. At the same time weed management is utterly essential, as without it weeds would overrun crops within a few years, dramatically reducing yield. Integrated weed management (IWM) is where, physical (e.g. mechanical hoeing), chemical (i.e., herbicides), biological (e.g. biological control) and ecological (e.g. rotations) techniques are used in an integrated and symbiotic manner. Integrated Weed Management is the approach recommended by the international weed science community. * To be published in Encyclopedia of soils in the environment (2nd edition), January 2023; currently available in Reference Module in Earth Systems and Environmental Sciences