Measuring crop yields on a community scale
1938
Reynolds, F.S. | Coldwell, A.E.
A method of measuring crops and grass yields while still in the field is needed. The farm practices, such as furrowing, ridging, contouring, and terracing, on ranch and farm lands need to be evaluated. A method of calculating yields was perfected. The method is based on securing a large number of small samples uniformly distributed so that all parts of the field are proportionally represented. The samples are weighed and yields calculated to an acre basis. On fields from 80 to 640 acres, one sample should represent not more than from 3 to 5 acres. Each field to be surveyed should be observed for kind of crop, shape and approximate size, and a route of march to obtain samples decided upon. The actual samples should be chosen in such a way that the human element is reduced to the minimum. The more uniform the crop, the more accurate the calculated yield will be. Therefore, fewer samples are required from the heavy yielding fields, which are also uniform, than from spotted and light yielding fields. Calculated yields may safely be said to be within +/- 10% of the actual yield. Farmers' estimates are not sufficiently accurate to be used as a yard stick in measuring the value of soil conservation practices. One man can measure the yield on 300 tO 500 acres of grain sorghums a day.
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