Within the realm of farming there can be a lot of discrepancy amongst the effectiveness of different cultural practices. Things like natural vs synthetic fertilizer; fertilizer application timings; crop protection practices; and even tillage vs no-till. Most practices in agriculture have a ton of hidden variables, and even ones that you identify can change drastically based on said variables, such as weather; soil type; drainage, etc. The consideration of tillage options can be a very tough one because all of the variables at play cause research which can support yield boosts in either direction. Tillage aims to alleviate compaction through physically breaking up the soil. In addition, it aims to encourage the decomposition of the crop residue left behind by harvesting the crop that was grown and harvested there.
Why do we want to get rid of compaction? Well, the short answer is that compaction can make it difficult for a plant to grow. By making the soil more dense, the plant roots have a harder time initially establishing, as well as growing further into the soil horizontally, and deeper, vertically. This can disable the plant from obtaining the required water and nutrients to grow, and most certainly will at least keep it from reaching its’ full potential in terms of growth and yield. In addition, it can also create an anaerobic environment in which some beneficial soil organisms which help to process nutrients cannot survive in.
Why do we want crop residue to break down as much as possible? There are a couple of reasons, not limited to what I mention. So, firstly, with crop residue sitting on top of the soil (corn/soybean/wheat leaves and stocks), water and other nutrients (applied or naturally found there) can be trapped on top of the residue which puts it at risk of being lost to the environment through volatilization and evaporation. Where do we really want it? As part of the soil, broken down and dispersed throughout different soil horizons so that it is available for the plants to pick up and put towards growth. With this organic matter present throughout the soil, the soil gains structure. In simplistic terms, it acts as a glue to hold different soil particles together, spread apart a little (depending on the particle size), which also allows for water pathways to form throughout the soil.
So why doesn’t everyone till as much as possible? Many reasons exist, but I’ll just highlight a few:
-The cost of equipment, labor, etc
-Some land needs coverage in order to keep the soil from being destroyed by the environment! Sounds extreme doesn’t it? Well, an example where this happens is not too far off, in Port Burwell, Ontario. The reality for a lot of farmers is that their land is extremely sandy. This is referred to as “blow sand” by the farmers in this area. Without crop residue or a cover crop (rye, wheat, etc) left on after a crop harvest, the topsoil is very susceptible to blowing away. This is also compounded by the inherent wind risks from this area, being so close to the lake.
-Repeated tillage to the same depth; in the same direction; at the same angle…it can create a “plough pan” or “hard pan”. This is a compaction but occurring below the soil surface. With the creation of a hard layer, even fields that are tiled to disperse excess water will turn into a pond in a hurry. All of the water becomes trapped above that layer, even if the soil above is structured properly to filter it. While this seems like common sense, it is not realized by all farmers. For example, a farm not too far away from home has been cultivating and ploughing with the same implements very intensively and often for quite a few years, and with this year being as wet as it was, it really showed, placing a lot of their crop in mud pits. My grandpa pointed out to me the frequency in which their land is worked, and suggested that a fix to their problem would be a round of deep tillage. This deep tillage would require a lot of horsepower to cut through the soil so far below the surface, but would aim to break the hard panned soil and allow the flow of water and nutrients to carry through deeper into and throughout the soil profile.
Below are pictures of us working in a customer’s field which was quite a mess this year. It resulted in burying a combine when we advised him to have us wait until the ground was frozen, and he urged us to try prior. Even after things had cooled off, the tractors managed to find some mud! I almost got stuck as well pulling a full load of corn out. The pictures are a little difficult to make out, but I thought I’d include them. This demonstrates the importance of soil caretaking and pairing with the correct cultural methods! Enjoy!