Thinking about a new way to assess soybean stands?
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EmailNew and more efficient ways to assess soybean stands would increase the likelihood of getting stand counts done when needed. How do high-tech options compare with the tried-and-true manual counts?
Numerous biological and environmental challenges can prevent a soybean seed from germinating, emerging, and growing to maturity, including disease, insect and wildlife damage, high-salt fertilizer injury, soil crusting, too little or too much soil moisture, frost damage, and others. If these factors impact stand shortly after planting, farmers should assess the stand count and decide whether replanting is economically beneficial. Growers should assess stands within one to two weeks of expected emergence to determine whether sufficient plant density exists to achieve maximum yields.
There are several methods for assessing stands as described in this MSU Extension article. In general, the more time it takes to conduct a stand assessment, the more accurate the measurement will be. Cost must be calculated in terms of time, labor and any external subscriptions or processing fees. If a method could be identified that minimizes investment in time and money while maintaining a relatively high degree of accuracy, more farmers and agronomists would conduct stand counts and thus be equipped to make important replant decisions.
A two-year research project was conducted by Michigan State University Extension educators to identify methods of conducting accurate soybean stand assessments that can be accomplished with less time and overall cost compared with labor-intensive manual counts. The hypotheses were that free technology would not be as accurate as fee-based technology, and methods relying on imagery taken from a considerable distance (i.e., aerial images), although least time-consuming per area, would result in the least accurate stand counts while methods using close-range assessments will result in the most accurate counts.
Four methods of stand assessments were conducted at multiple locations involved in the Soybean On-Farm Research Program in 2024, and a fifth method was added in 2025. Methods included: 1) manual counts (the benchmark); 2) BeanCam free smartphone app; 3) Smart Stand fee-based web app for video analysis; and aerial imagery with subsequent subscription-based stand count analyses conducted by 4) Agremo and 5) Sentera. All assessments were taken between VC and V2 to minimize overlap between adjacent plants. Sites included a variety of scenarios (crop row spacings, seeding rates, level of previous crop residue on the surface, degrees of weed control, etc.) to test the rigor of each method.
Results showed a moderate positive correlation between manual counts and BeanCam app estimates (0.3122, p=0.0003) but a poor correlation (<0.30) between manual counts and all other methods. There were also moderate positive correlations between target seeding rates and manual counts (0.4636, p<0.0001) and Agremo aerial imagery analyses (0.6125, p<0.0001).
Even though alternative methods were generally faster than manual counts, fee-based ones were somewhat costly and none provided sufficiently accurate soybean stand estimates. Further investigation taking into account soybean row spacing, seeding rate, and level of weed or cover crop pressure will need to be conducted to determine whether any of these technologies can provide satisfactory stand count estimates under specific conditions.
So don’t throw that hula hoop out just yet.
This article was produced by a partnership between MSU Extension and the Michigan Soybean Committee. This article was first published in the Michigan Soybean News magazine