Update:
Final stand counts were taken prior to harvest. All plots were harvested between September 23 and November 20. The price of soybean seed and the price per bushel were used to calculated net income per acre.

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Introduction
Soybean population plots were planted on four University Research and Education Centers (REC) and on one farm in Carroll County. Planted populations were 80, 100, 120, 140, and 160 thousand plants per acre. At the Wye REC, an additional population of 50 thousand plants per acre was added.

Final Stand Counts
Stand counts were taken prior to harvest; this number of plants present in the field at harvest time was converted to a percent of the planted population. The average percent of planted plants at harvest across all populations was 56% (Wye), 63% (Upper Marlboro), 70% (Carroll), 75% (WMREC), and 86% (Beltsville). Some of these numbers were a bit lower than expected, and most likely due to wet spots, weeds, and variety performance. Even though some sites had a low survival rate, this did not correlate to a lower yield. Within each site, stand counts were fairly consistent across the planted populations (Figure 1). Planted population was not significant; one population did not lose more plants compared to another planted population.

Yield
The following yield ranges were seen at each of the sites: 59-63 bu/A (Beltsville), 52-56 bu/A (Carroll), 65-68 bu/A (Upper Marlboro), 67-71 bu/A (WMREC), and 66-80 bu/A (Wye). Figure 2 shows the yield at 13.5% moisture for each site. Yield was not statistically significant between planted populations, indicating that for these sites, a lower population could have been planted and yield could have been maintained.

Net Amount Per Acre
The gross amount per acre was calculated by multiplying the soybean price per bushel by the number of bushels per acre harvested. The net dollar amount was then calculated by subtracting the seed cost from the gross amount. Seed prices are the price before any discounts would be applied, and varied by site (Table 2). At the time of harvest, soybeans were an average of $11.17/bu on the Chicago Board of Trade. At four out of the five sites, the highest net per acre was at a lower population than the lowest net per acre (Table 3). The highest net per acre was at the planted populations of 80,000 (Wye), 100,000 (Carroll), 120,000 (Beltsville and WMREC), and 140,000 (Upper Marlboro). The lowest net per acre varied across the five sites.

Summary
Yield results indicate that optimum yield can still be achieved at lower populations. Based on this research, the planted population at the five sites in 2020, as well as two sites from 2019, could have dropped their populations down between 80,000 and 140,000 plants per acre, and still maintain optimum yield as well as an acceptable net amount per acre.