Indiana soybean planting in 2023 is following the same track as 1988 and 2018, which could be devastating or bin busting! As you may or may not recall, 1988 was one of the worst droughts we have experienced. Indiana soybeans yielded 27.5 bu/ac, which was 11.5 bu less (30% reduction) than the trend yield (39 bu/ac). The only year with a faster pace was another drought year—2012. Late season rains saved the 2012 crop and Indiana yielded 44.0 bu/ac (5.8 bu below yield trend, ~12% reduction). Soybeans were planted at a fast pace in 1991 due to dry and drought conditions, but the yields were nearly unaffected (3% less than trend).
Figure 1. Early soybean planting progress in Indiana from 1988, 1991, 2012, 2018, 2020, 2021, and 2023. Five-year average from 2018 to 2022. Adapted from USDA-NASS, 2023.
Indiana has had six years that soybean planting progress was substantially faster than the five-year average (Figure 1). Three of those years were drought years (1988, 1991, 2012) while the other years (2018, 2020, 2021) were yield-breaking years!
Timely planting of soybean (some may call it “early planting”) is the foundation for building great yield potential of soybean. Soybean usually develop more trifoliate nodes (and thereby, mainstem pods later in the season) with plants that have shorter internodes and more reproductive branches. These soybeans usually intercept more sunlight, accumulate more thermal energy, close the row earlier in the season, and extend reproduction duration. All of these physiological effects provide promise of high yields, which seem to match the advanced planting progress of 2018, 2020, and 2021. In fact, Indiana soybean yield record was surpassed with each of these early planting years (57.0, 57,5, and 59.5 bu/ac, respectively).
Soybeans are rated 70% good to excellent as of May 30th, which speak to the number of timely planted fields that were able to get well established (i.e., plant population and root system). These soybeans will continue to root deep with benefits for later season water needs during seed fill. A few of the early (~early to mid-April) and later planted (~late May) fields have or will be struggling with adequate stand establishment and early season development. These fields will be more prone to negative yield effects as the return of rain is delayed. At this point, we have a lot of season left to make up for shortfalls in soil moisture.
