Abstract: Method and apparatus for calibrating a material-spreading applicator. A broadcast spreader or planter is moved over a field for a measured length. The amount of fertilizer or seed which the applicator would have spread over the surface while it was so moved is caught. The area on which the caught material would have been spread is calculated and the caught material is weighed. Thereafter the weight of the caught material is divided by the calculated area. Another aspect of the invention comprises a weighing apparatus having an elongate arm with a weight slidable therealong. A container having a conical shape is mounted on one end of the arm and a support is pivotally attached to the arm between the container and the weight.