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Martinsville, Ohio | "Estimating yields of soybean fields before harvest may be useful for planning crop storage, making marketing decisions, determining management effects or addressing damage from crop hazards. To accurately estimate soybean yield three factors must be measured a) number of pods in a known area, b) number of seeds per pod and c) seed weight. The more precise these components are measured the more accurate the yield estimate will be. Yield estimates are also more accurate the closer plants are to reaching physiological maturity. However, yield estimates are generally only accurate +- 25% of actual yield. Yield estimates made prior to maturity can be done by counting yield components rather than weighing using the following procedure: 1. Count the number of pod-bearing plants in 1/1,000 acre. (For 7-inch rows count plants in 75 ft of row, 15-inch rows count 35 ft and 30-inch count 17.5 ft of row.) 2. Determine pods/plant by counting number of pods (containing one or more seeds) from 10 plants selected at random. Divide total pod number by 10 to get pods/plant. 3. Calculate the estimated yield using the formula: (no.plants) x pods/plant) ÷ 60 = bu/acre Example: If the number of pod-bearing plants in 1/1,000 acre was 140 and the average number od pods per plant was 30, the estimated yield would be: 140 x 30 ÷ 60 = 70 bu/acreThis formula assumes an average of 2.5 seeds/pod an average of 2,5000 seeds/pound and 60 pounds/bushel. Repeat steps 1-3 several places in the field to improve the accuracy of the yield estimate. 4. If the number of beans/pod and/or the number of beans/pound are known or are measured then instead of step 3 use this formula: (no. plants) x (pods/plant) x (beans/pod) ÷ (no. beans/lb) x (.06) = bu/acre. Example: If the number of pod-bearing plants in 1/1,000 acre was 140, the number of pods per plant was 30, the beans/pod was 2.7 and there were 2400 seeds/lb, the estimated yield would be (140 x 30x2.7) ÷ (2400 x .06) = 78.75 bu/acre.Caution: Actual soybean yield determinations can only be made at harvest by accurate area and grain weight measurements. " | |
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Soybean Yield Formula
