Integrated Weed Management in field crops: sustainability and practical implementation.

Integrated Weed Management (IWM) is a sustainable approach to the management of weeds by combining all available weed control techniques, including preventative measures, monitoring, crop rotations, tillage, crop competition, mechanical and physical control, herbicide rotation, herbicide mixtures, biological control, nutrition, irrigation, burning, etc. in a way that minimizes economic, health, and environmental risks. The first step in IWM program is to monitor the fields for signs of weed infestation or potential weed problems. Proper weed management involves a thorough survey of each field after crop harvest to identify major weed species in the field. When an annual crop (maize, sugar beet, soybean, wheat, etc.) is to be grown in the field in the following year, this information is used to assess the importance of each weed species and to select the appropriate management strategy to be used for the coming crop. In annual crops, fields are also monitored after the crop has emerged, to assess the effectiveness of the selected management alternative and whether additional management measures are needed. For planting perennial field crops, such as alfalfa, an assessment of weed species composition is conducted after harvest of the previous crop, to determine the appropriate management alternative to be used during the establishment. In an established crop, fields are monitored to determine the need for additional measures to manage annual, biennial and perennial weed species.