Figure 2. Calibration equation to estimate forage mass. Y = herbage mass (lb/acre). This value comes from the hand-clippings. a = intercept of the equation with the X-axis. b = slope of the equation. x = values of your indirect measurements. r2 = measurement to assess the goodness of fit of the equation.
Calibration equation includes intersection of indirect measurement on the x-axis and dry matter from hand clippings on y-axis.

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