KSUSoyYieldCalc

An app to estimate soybean yield before harvest using conventional approach.

KSUSoyYieldCalc is a native Android application that solves the problem of yield estimation of soybean before harvest following conventional approach.

The Soybean Yield calculator has only four inputs for predicting the final yield:

1. Plant population (plants/acre). This component can be estimated by counting the number of plants in a 21-inch row length for 30” row spacings (1/10,000th area), and by multiplying that number by 10,000;

2. Pods per plant. This factor can be obtained by counting all pods per plant in the 21-inch row length (for example 10 plants equal 100,000 plants/acre);

3. Seeds per pod. A good average number is 2.5 seeds per pod, but the range presented is from 1 to 4 seeds per pod;

4. Seed size. Seed size typically ranges from 2,000 (large) to 3,500 (small seeds) seeds/lb, with an average of 2,800 seeds/lb.

The last factor “seed size” is the same as the one presented in the “conventional approach.” This factor normally varies from 2,400 to 3,200 seeds/lb. If the conditions until harvest will be favorable, then the “seed size” component should be a lower number (e.g., 2,400 seeds/lb). If conditions are likely to be unfavorable, resulting in a short seed-fill period, then this factor should be higher (e.g., 3,200 seeds/lb). This factor will be ultimately determined as the crop approaches maturity, but an estimation is needed considering the importance of this factor for influencing final soybean yields.

Here is one example of how to use this App:

INPUTS:

1. Plant Population: 12 plants (measured at 12 sites within the field) in 21-inch row length x 10,000 = 120,000 plants/acre

2. Pods per plant: 24 pods per plant, enter individual pod number per plant (average of 10 plants in 21-inch row length)

3. Seeds per pod: 3 seeds per pod (estimation)

4. Seed size: 2,800 (assuming “normal” conditions during seed-fill period)

OUTPUT:

Final Yield estimation: 43 bu/acre