For better yield and quality, controlling weeds during the critical
period of crop growth are important. Identification of the critical
period for weed control (CPWC) in major crops is one of the first
steps in designing a successful integrated weed management
(IWM) program (Swanton and Weise, 1991; Knezevic et al., 2003)
and use of the critical period threshold model will assist in
improved farm level decision making