In the field yesterday, I came across something interesting. Last fall, the end rows of a no-till field had been gone over with a disc ripper to break up soil compaction. I have been in this field several times since this ground was tilled, but I didn’t notice anything unusual until yesterday when I saw patches of loose soil as shown below.

Photo – J. Pike

At first, I thought these spots were caused by animals, but after closer examination, this was from clods of soil that had broken down over the winter from freezing and thawing. This is not unusual, but with the soil being so dry, it is much more noticeable. Note how the soil looks like coffee grounds in my hand in the picture below.

Photo – J. Pike

Those smaller “clods” are soil aggregates, made of several small soil particles (silt, clay, and a little sand) glued together by beneficial processes in the soil as a result of no or limited tillage over time. In the middle of the ridges, made by ripper where water had run or sat, the soil aggregates have broken down quicker and formed a crust on the surface of the soil. This is shown by the cracks where my blue ILSoyAdvisor soil depth finder is stuck in the ground.

Photo – J. Pike

The next picture shows the crust when I dug a piece out of the ground. The crusted soil surface greatly reduces the ability of water that can get into the soil during a rain, so unfortunately, this can lead to more runoff of the water. This can cause several problems, but with the soil being so dry, we need all the moisture we can to get in the soil.

Photo – J. Pike

It is a common myth or misconception that tilling the soil allows more water to get into the soil. This simply is not the case. The last picture is a piece of soil dug up in an area of the field that was not tilled last fall. This soil is well aggregated at the surface and the roots of winter annual weeds are also helping the water infiltration process. The soil appears darker because the level of moisture is higher (not because of any other magic).

Photo – J. Pike

The moral of the story is that tillage was used on the end of this field where traffic from grain trucks had compacted the soil, and tillage in this area made some sense. However, tillage of the whole field did not, especially with it being extremely dry and more water infiltration could have taken place. Hopefully it will rain on a regular basis this spring and summer so the reduced water holding capacity of tilled fields like this will not be a factor. If we keep missing rain, there could be a drastic difference between tilled and no-tilled fields during the growing season since it is much drier than normal especially as we dig down deeper, where it is exceptionally dry for this time of year.