John Deere transformed farming with his first steel plow in 1837. Deere’s moldboard plow design was a massive improvement over previous tools for cutting and turning the prairie soil. Plowing was necessary in those days to eliminate the weeds and native plants competing for space, water, sunlight, and nutrients. This set the stage for many modern farming advancements that followed. John Deere just recently ended production of the moldboard plow in February 2023 – marking the end of an era.
There are still many plows around in the country, but over the past 50 years they transitioned from wide scale use in to more of a specialty tool. Plows are too aggressive for modern farming practices today. They completely turn over the soil leaving it vulnerable to water or wind erosion without plant residue or roots to anchor the soil. The Dust Bowl of the 1930’s was a lesson in what can happen from wide scale plowing during a major drought. Conservation and tillage practices have been evolving ever since.
One of the biggest shifts in farming over the past 20 years with tillage has been to eliminate it all together. Today, no-till farming is a preferred farming practice throughout the Corn Belt, and it continues to grow in popularity. The crop production and environmental advantages of no-till have been widely covered in many of our previous newsletters as well as numerous farm media outlets, extension outreach publications, and USDA Service Centers, so I won’t go into those details here.
The momentum for more no-till farming is important progress, but it’s also worth looking at how tillage equipment has improved over the years acknowledging the benefits it can provide. The decision of when or if you should use tillage on a farm is not as clear-cut as some make it out to be.
Here are some of the main goals of tillage:
- Warm up topsoil faster in the spring for earlier planting
- Incorporate fertilizer, manure, lime, herbicides, or layers of stratified fertility zones
- Chop up residue from previous crops
- Break up soil compaction layers
- Level a field
- Reduce crop diseases
- Weed control – especially on organic farms
Modern tillage equipment is much more efficient and reduces soil disturbance and erosion compared to the equipment from the past. These implements have countless options for shank, coulter, disk, and harrow configurations with adjustable depths and pitches.
The terminology for tillage tools can be confusing. Below is a list and description of the types of tillage we see used in this area:
- Disk – Uses two rows of concave angled disk blades, hence the name “tandem disk”. Disks are an aggressive tillage option that incorporates a large amount of residue. They can compact the soil just below the disk blade depth. The greater the angle of the disk blades, the more compaction pressure.
- Field cultivator – Has rows of shanks or teeth and often has a spike drag or something similar on the back end to firm and level. They are designed to lift the soil, mix it, and eliminate weeds. They don’t chop and size residue.
- Soil finisher – Kind of a mix between a field cultivator and a disk. They have disc blades in the front, shanks in the middle, and a finishing drag or rolling basket in the back.
- Rippers – Designed for deep tillage, including disk rippers, chisel plows, and in-line rippers. They are usually used in the fall. Disk rippers and chisel plows are aggressive as they bury a lot of crop residue, but some of the in-line rippers do minimal disruption at the surface.
- Vertical till – Uses straight waved blades set at shallow depth. Vertical tillage is supposed to fluff or open the soil by lifting the soil at high speeds with the waved blade moving it vertically and leaving it directly behind the blade. It also chops up the residue. They don’t do a great job of leveling, but they leave most of the residue on the surface.
- High speed disk – These types of machines are made to run fast like vertical tillage machines, but also bury/ mix in residue and level. The blades are set at a slight angle, so they are more aggressive than vertical till. They can leave more or less residue on the surface depending on the settings.
- Strip-till – Narrow strips are tilled with the area between the rows left undisturbed. Fertilizer can be applied into the strip as part of this tillage pass. Crops are planted directly into the strips.
Before doing any type of tillage on a farm, the soil type, slope, and current soil conditions should be considered. Tillage on wet or steep slope soil is never recommended. When used responsibly, modern tillage practices remain helpful to a lot of farming operations. I don’t see tillage going completely away anytime soon, but it will continue to be reduced and refined to protect long-term soil health.
This article originally appears in the Summer edition of Today’s Land Owner, authored by Chad Husman, AFM
