In past years, the end of the calendar year for agronomists and producers has been denoted by the beginning of the winter meeting season at the conclusion of the growing season. Like many things in 2020, the meeting season is a bit different this year. The in-person meetings have been canceled or replaced with virtual experiences, so the sharing of observations and lessons learn from the 2020 growing season is very different. So, what was some of the big trends in soil testing for 2020 and did the agronomy fears at the conclusion of 2019 occur? We’re glad you asked!
The late fall of 2019 soil sampling continued uninterrupted into an early spring of 2020. Traditionally soil sampling increases at a rapid rate in late September and builds though October. The sample volume reaches a peak in mid to late October, then begins decreasing sometime late November. Sample numbers continue to slowly decline until weather conditions stops soil sampling in mid to late December. The mild 2019/2020 winter, combined with the late 2019 harvest, led to a slow ramp up in mid-November and samples continued to arrive at the lab at a steady rate all winter. The was no clear end to fall 2019 sampling, nor a defined beginning of 2020 spring sampling. The fall 2020 soil sampling season has been, and continues to be strong, following a more “normal” sampling season. Something that has not happened 3 or 4 years.
One of the main concerns from the wet fall of 2019 was the potential for soil compaction. The wet year set the stage for compaction to occur during both the 2019 planting and fall harvest. The wet fall of 2019 prevented proper fall tillage to correct compaction from 2019, let alone compaction created in 2018 or 2017. The preplant expectation was that soil compaction would negatively impact on yield in 2020, especially if the weather pattern turned dry. For some areas 2020 was dry, but the reports of soil compaction related crop issues were not as severe as expected, leading to near average yields for most growers. There are many theories as to why the impacts of soil compaction was less than expected, they mostly revolve around overall improvements in soil management leading to improved soil structure in recent years. Producers took what preventative steps they could to reduce the impact of soil compaction in 2020 and it appears to have worked. Those areas that were unable to plant in 2019 were able to perform deep or primary tillage in the late summer early fall before the wet conditions began.
Also, many growers focused on earlier maturing varieties to avoid another late fall. This was a positive management strategy as many portions of the ALGL trade region ran behind schedule on GDU accumulation in the summer of 2020. With the timely 2020 harvest allowing for well timed soil sampling and fall field work, along with growing positively in the grain markets, the overall optimism for improved farm incomes in the coming years is growing. While we may want to forget 2019 for the agronomic challenges and likewise push 2020 from our memory due to Covid 19, that may not be wise for future management.
Inconstancies in soil sampling can lead to variation in soil test values over time. Challenging weather conditions in the spring and/or fall soil sampling seasons from 2017 though the spring of 2020 may lead to slight variations in soil test results. In the future when comparing soil test data sets that include samples collected in this time frame, the challenges of these year may shed some light on soil sample variances. More frequent soil sampling can reduce the impact of these variances by adding more data points to the analysis. Repeated soil sampling provides a check and balance approach to soil fertility management.
While we all have been impacted by the Covid Pandemic, the bright point was the timely fall harvest leading to some very good conditions to complete fall soil sampling, perform fall tillage in good to near idea conditions, plant cover crops, and make timely fertilizer/lime applications. The condition of the soil samples coming into the lab were some of the best sample quality we have seen in the past 3 to 4 years. Hopefully the fall soil sampling season of 2020 will provide some stability to long terms soil fertility management.