This document discusses weed management systems for field crops. It outlines different weed management systems including those for small grain crops and row crops. The key components of a weed management system are prevention, mechanical control, cultural control, biological control and chemical control. Prevention involves using weed-free seeds and equipment. Mechanical control involves tillage. Cultural control involves practices like crop rotation. Biological control uses organisms to control weeds. Chemical control can use herbicides that are broad spectrum, selective, contact or systemic. An integrated weed control system combines these different approaches.