Effect of botanical composition calibration on the accuracy of undisturbed sward height and comparative yield method techniques for herbage mass estimation in tropical heterogeneous pastures

This study aimed to evaluate the influence of botanical composition calibration on accuracy undisturbed sward height and comparative yield method (CYM) techniques for herbage mass estimation in tropical heterogeneous pastures. Two studies were conducted using two grazing systems based Herbage was estimated CYM within quadrats (SHQ) or at a set standard points paddocks (SHP). SHQ had higher adjusted R2 when calibrated with Urochloa brizantha cv. Marandú (U. brizantha) proportion compared simple model (0.75 vs 0.68), while RSE lower (0.18 0.21). The increased (0.63 both residual means decreased (−2.30 −0.05 0.22 0.20, respectively) SHP U. brizantha. It also resulted reduction mean squared prediction error (MSPE) CYM, SHQ, SHP, respectively. allows pastures than height, irrespective calibration. However, positive effects models from prediction.