Grain sorghum [Sorghum bicolor (L.) Moench] has been a valuable crop for the southern Great Plains due to its ability to overcome the high temperatures and sporadic rain events common in the region. Optimizing production practices has always been critical for grain sorghum to overcome these environmental challenges. In response to sugarcane aphids (SCA), a detrimental pest in grain sorghum production, common agronomic management practices rapidly shifted with no regard to how such changes would affect overall production. This research is aimed to evaluate the effects of the hasty management changes on grain sorghum plant stands and yields in Oklahoma. Trials were established in 2016 and 2017 at the Northcentral Research Station in Lahoma, OK, and the Efaw Research Station near Stillwater, OK. Four planting dates, two hybrid types, and insecticide applications were evaluated on their impact on early‐season stands and crop yield. Findings showed that planting date had the most consistent impact on sorghum yields, across hybrid types and insecticide applications. Planting in April resulted in higher yields in 2016. However, results from 2017 showed that cooler soil temperatures, as measured by Mesonet stations at each location, can still limit yield when grain sorghum is planted too early. Early‐season plant stands followed the same trend as crop yields, with the highest early‐season stands occurring in the same period as highest yields. Yields and stands consistently decreased with later planting. It was also during these later planting dates that hybrid selection and insecticide applications were found to have a significant impact on yield.

Soybeans often encounter several in-season stressors that can alter retention of reproductive structures. To understand soybean response to structural losses through altered growth parameters—and, ultimately, yield—a field trial was established in Bixby, Oklahoma, in 2019 and 2020 and Perkins, Oklahoma, in 2019. Removal of reproductive structures occurred at full flower (R2), the beginning of pod development (R3), and the beginning of seed development (R5) and at three locations on the plant (top third (T), middle third (M), whole (W)). The impact of flower removal on yield at the R2 and R3 stages did not significantly differ from that in non-treated soybean. Pod removal as late as R5 from the upper fruiting positions (T) had a lesser impact on overall yield, with R5:T showing a reduction in seed number of 860 seeds plant⁻¹, whereas R5:M was 1921 seeds plant⁻¹ below the non-treated soybean. The middle portion of the mainstem was the location where the loss demonstrated was paramount at R5, as this region is a large sink and major contributor to yield. Late-season, stress-negating yield recovery, depending on the severity, may indicate that management practices should anticipate physiological limitations for stress, as well as the potential for relative yield recovery and yield improvement.

Farmers have been interested in using foliar‐applied nutrient products to increase soybean [Glycine max (L.) Merr.] yield since at least the 1970s, despite limited evidence that these products offer consistent yield increases when used prophylactically. Recently, interest in foliar fertilizer products for soybean production has been renewed, likely related to elevated soybean prices. Over the 2019 and 2020 growing seasons (46 site‐years), agronomists in 16 states collaborated to test six foliar nutrient treatments (commercial mixtures of macro‐ and micro‐nutrients) on soybean grain yield and composition. Soybean grain yield and composition differed among sites but not among foliar fertilizer treatments. Results show that prophylactic foliar fertilization is likely to decrease the profitability of soybean production. Foliar fertilizer products tested in this study and similar products should not be recommended to U.S. soybean farmers in the absence of visual symptoms of nutrient deficiency.

The implementation of cover crops in crop rotation is a suggested soil health practice. As cover crops are not harvested and sold, they do not directly provide monetary gain to producers. Therefore, it is imperative that planting cover crops does not negatively affect the subsequent cash crop. However, there is no overall consensus in the literature regarding the effects of cover crops on cash crop yield. To better understand the effects of cover crops on soybean growth and yield in Oklahoma soybean systems, trials were conducted in Bixby, OK, in 2019 and Perkins, OK, in 2019, 2020, and 2021. The objectives of these trials were to (1) determine how different cover crop mixes affect soybean growth parameters and (2) determine if cover crops significantly influence soybean seed yield. Treatments within the trials included six cover crops and a fallow treatment. Soybeans were planted after the termination of the cover crops. Yield and growth parameter data were collected after harvest. No significant differences or consistent trends were detected in the yield among treatments. While cover crops had a significant impact on the number of three- and four-bean pods, no other differences in the growth parameters existed, and they never translated into significant yield differences. Based on our data, cover crops would not benefit the overall cash crop production in the continuous cover crop soybean system in Oklahoma. However, the fact that cover crops did not consistently or significantly reduce soybean yield allows growers to explore other benefits, such as weed management or soil health improvement.

Desiccants have been used in many crops to aid in late‐season dry‐down, hasten harvest, and improve harvest efficiency. Glyphosate, the primary desiccant used in grain sorghum [Sorghum bicolor (L.) Moench] production, can be effective at drying the crop but has been noted to have issues completely desiccating plants. The objective of this study was to evaluate the impact of various desiccant products on grain sorghum dry‐down and yield. Field trials were conducted at Goodwell and Stillwater, Oklahoma, in 2017 and 2018. Five desiccation treatments were applied at approximately 30% seed moisture, with dry‐down time, grain yield, and foreign material evaluated in this study. It was found that the use of desiccants aided in a more rapid and greater dry‐down of the sorghum plant in both Goodwell and Stillwater locations, with the glyphosate and glyphosate/saflufenacil applications showing the greatest drydown. As opposed to plant moisture, grain moisture was not consistently influenced by desiccation treatments. Due to mild late‐season weather, grain yield was increased from the use of desiccants at the Stillwater location primarily as a result of increased harvest efficiency. Overall, it was found that both glyphosate and the combination of glyphosate with saflufenacil provide better dry‐down compared with saflufenacil, carfentrazone, and sodium chlorate desiccants alone. In most sorghum production systems, glyphosate would be adequate in terms of dry‐down and control of late‐season weeds; however, if saflufenacil were to become labeled, it could provide an option for growers in certain production systems, such as those with problematic weeds.