The free app weed-determination is for the rapid and unambiguous determination of 137 different weeds in sugar beets and 35 grasses. Supported by many pictographs (pictures) the determination is based on plant organs. Individual weeds and grasses are described in detail (germination, leaves, stems, flowers, etc.) and illustrated with images at different stages of development and several details. This app is a joint development by LIZ, BISZ, IRS, IRBAB / KBIVB, ITB, Nordic Sugar, British Sugar, AIMCRA, BETA and SFZ / CBS.