Non-chemical methods of weed control: benefits and limitations

Non-chemical methods of weed control will become increasingly important in Europe due to a lack of herbicides, increasing resistance and a new European Union (EU) requirement for use of IPM. Compared with herbicides, non-chemical methods tend to be less effective, more variable, more expensive, may not reduce the requirement for herbicides, provide little visual evidence of success, may have adverse environmental implications and are often more complex to manage. Such control methods often have mean efficacy levels equivalent to a poor herbicide, but at a premium price. It is postulated that these reasons explain the limited uptake of IPM worldwide, not only for weeds, but for pests and disease control too. It is suggested that, if the primary objective of IPM within the EU is to reduce pesticide use, then it might be preferable to have this as a specific objective, rather than the more malleable concept of IPM.