Critical period of weed competition

• Critical period of weed competition is defined as the shortest time span during the crop growth when weeding results in highest Economic returns.
• The critical period of crop-weed competition is the period from the time of sowing up to, which the crop is to be maintained in a weed free environment to get the highest economical yield.
• Generally in a crop of 100 days duration, the first 35 days after sowing should be maintained in a weed free condition.
• There is no need to attempt for a weed free condition throughout the life period of the crop, as it will entail unnecessary additional expenditure without proportionate increase in yield.
• Critical period of weed competition for important crops ae as follows: