And the Yield Is?
August was known as “weed” month to the Anglo-Saxons because in the northern hemisphere weeds grew fastest during the month. August now might be better known as “yield” month for the proliferation of yield estimates. On August 9, the DTN Digital Yield Tour estimated corn would yield 189.5 bushels on average in Nebraska and soybeans 55.6 bushels. USDA estimates released August 11 forecast yields of 185 bushels per acre for corn and 58 bushels for soybeans. The Pro Farmer Crop Tour 2023, which visited fields in eastern Nebraska last week, calculated an average yield of 167 bushels for corn and a soybean pod count of 1,160 (in a three-by-three square foot area). Also last week, UNL agronomists using their Hybrid-Maize Crop Model updated yield estimates for ten irrigated and seven dryland locations in Nebraska. The model suggests corn yields at six of the Nebraska irrigated locations have a greater than 75 percent probability of producing the long-term average yield. In contrast, five of the seven dryland sites have less than a 20 percent probability of producing average yield.
Comparisons of crop conditions this year to past years can offer insights into the accuracy of these estimates. Figures 1 and 2 plot corn and soybean conditions rated good or excellent this year compared to the previous five years. As of August 20, corn rated in good or excellent condition was 61 percent and soybeans 58 percent. Last year for the same week 42 percent of the corn crop and 46 percent of soybeans were rated in good or excellent condition. After trending lower through June, conditions this year recovered and stabilized. Yet they remain worse than that typically seen in late August. Between 2018-2021, excluding 2022 due to drought, 74 percent of corn and soybeans on average were rated in good or excellent condition for the same week.
FIGURE 1. CORN ACRES RATED GOOD OR EXCELLENT, 2018-2023
Source: USDA National Agricultural Statistics Service
FIGURE 2. SOYBEAN ACRES RATED GOOD OR EXCELLENT, 2018-2023
Source: USDA National Agricultural Statistics Service
Last year’s good or excellent ratings were unusually low, and yields reflected it. The average corn yield, 165 bushels per acre, was down 15 percent and the average soybean yield, 49 bushels, was down 22 percent compared to 2021. For perspective, corn yield between 2018-2021 averaged 185 bushels and soybeans averaged 59.5 bushels. Improved conditions this year should result in higher yields, but because conditions are worse than typical, they are likely to be less than the 2018-2021 averages. Thus, the USDA and DTN yield estimates for corn seem optimistic, while the Pro Farmer Crop Tour calculations seem overly pessimistic. Estimates of soybean yields appear to be closer to the mark, but still lean optimistic.
Crop conditions are likely to deteriorate given last week’s extreme heat and the forecast for more hot temperatures next week. Weeds seem to be the only plants which thrive in such conditions—as the Anglo-Saxons noted. Crop yields and production in Nebraska should be better than last year, but will again be below par.
