I just checked out the 7-, 14-, 30- and 60-day rainfall accumulation maps on the National Weather Services website and observed amazingly extensive blue and green areas across Illinois and a wide swath of other colors over central and eastern Corn Belt states—representing 200% to 500% of normal precipitation during all time frames!

According to State Climatologist Jim Angel, Illinois has actually been wetter during the last 6 weeks (June 1 – July 13) than during the same time frame in 1993, the year of the Great Flood. Visit the blog post here.

Not surprisingly, in between scrambling to plant, spray, sidedress, replant and re-replant etc., during the narrow to non-existent windows of opportunity, farmers have poured out their frustrations about the weather at Internet forums, coffee shops and dining room tables.

This editorial won’t resolve the most popular riddles, for example, when the relentless rains will end or why grain prices haven’t responded more bullishly, but it will explore some of the thoughts that have crossed my mind while pumping water, digging ditches and listening to frogs croak in my research plots.

Anyone who regularly drives down country roads has observed that spatial variation in crop growth is amplified this year and during other seasons with extreme weather (drought and excessive rain). This variation across fields is even more apparent during harvest or in the air—today you can buy a drone and take a look yourself from above.

Some of this variation is related to soil type and topography, but management also plays a role. For example, the striping of fields related to tile lines and uneven distribution of fertilizer and crop residue.

Farmers observe improved crop growth over tile lines and quickly conclude that lateral spacing should be narrower. Less thought is given to how soil management practices can be adjusted to improve tile performance. Water percolates to tile lines through macropores, and it is clear that practices such as tillage, wheel traffic and cover cropping impact the presence and connectivity of macropores. Farmers can enhance return on investment in tiles by managing for improvements in soil structure.

Many farmers spend freely in pursuit of establishing picket fence stands but give much less thought to yield loss associated with random wheel traffic and non-uniform distribution of fertilizer, herbicides and crop residue. One other major source of long-term spatial variation in soil productivity that is underappreciated is tillage erosion.

Tillage erosion is the actual movement of soil by tillage tools—the planing off of high areas and the filling in of lower areas. A growing body of research shows that tillage erosion often exceeds water erosion and that tillage erosion decreases the productivity of hilltops and back slopes more than it enhances low areas. Some innovative farmers have achieved major returns on investment by reallocating topsoil to thin areas, but the first step is to recognize the problem and stop the bleeding.

In conclusion, the variability appearing in our fields this season is very disheartening, but is also informative. I challenge you to look closely at the variation in your fields this year and identify opportunities for improved soil management and associated weather proofing of your farm.

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About the Author: Dr. Joel Gruver