Over the last two centuries tillage has developed from the use of hand tools to the use of complicated machinery. Here we will take you through the disadvantages of tillage and why every farmer and gardener should slowly start adopting conservation tillage. There are other options to prepare your garden soil and we will discuss some of them as well.
What is Tillage
Tillage is one of the oldest human activities dating back to ancient Egypt. It involves turning the soil manually or mechanically to prepare the soil for plant growth.
Over the last century, tillage has developed to become easier thanks to technological advancements. While it has gotten easier, it has become more disruptive.
Reasons Why Tilling is Used to Prepare the Soil
- As a way to control insects and pests
- Eliminate weeds
- Aerate the soil
- Improve moisture penetration
- Make it easy for seeds to germinate
- To facilitate root growth
- To mix organic matter into the soil
But the million dollar question is- is tillage good? -The bold answer is, no
Tillage has so many downsides. That’s why there is so much advocacy for conservation tillage. Considering tillage has been a major agricultural activity for centuries, many farmers are hesitant about no-tillage and other types of conservation tillage. Also, the farming machinery industry is huge and it’s not ready for this conservation since no tillage impacts the business.
Looking at research and the latest studies, tillage has so many downsides. This article covers the disadvantages of tillage.
Tilling vs. Plowing
While these two words are used interchangeably they are different.
Plowing is a type of tilling. Plowing is the intense and disruptive turning of the soil. It involves going deeper into the soil. Plowing leaves rough and uneven furrows and ridges while tilling leaves a smoother surface.
Types of Tilling
1/ Primary Tillage
This is the first tillage which is done immediately after a harvest or at the start of the planting season. It also refers to tillage done on virgin land in preparation for planting. Primary tillage goes up to 30 centimeters below and is done several times in a year.
Types of primary tillage include
- Deep tillage
- Sub-soiling
- Year-round tillage
2/ Secondary Tillage
Secondary tillage follows primary tillage to make the land ready for planting. The goal is to achieve a smooth tilth. Secondary tilling is not as disruptive and aggressive as primary tillage.
Why is Tillage bad? – 9 Disadvantages of Tillage on the Soil
1/ Soil Erosion
The first downside of tillage is soil erosion. Tillage involves turning and breaking soil into small particles, making soil particles prone to erosion. The loose particles are easily carried by wind and water.
Erosion of tilth is further enhanced by the nature of the surface. For instance, slanted lands are more prone to gravity erosion. Tillage removes the covering from the soil. When it rains the raindrops hit directly on the soil particles further accelerating erosion.
Tillage erosion leads to the loss of useful organic matter and nutrients. When there are strong winds or heavy rainfall, erosion also carries the seeds if the soil is still weak.
Tillage Erosion is Determined by
- The tools used
- Direction of tillage
- Heavy rainfall or strong winds after tillage
- Tillage depth
2. Habitat Destruction Underground
The soil provides a natural habitat for millions of microorganisms. Tillage kills, displaces, and exposes these organisms to the sun. Tillage also destroys the habitats that these microorganisms have built underground.
Soil organisms play a vital role in the decomposition of organic materials that enrich the soil and support nutrient recycling. While some microorganisms such as bacteria can survive tillage, bigger organisms such as helpful worms end up dying.
Tillage also accelerates the decomposition of organic matter by increasing biological activity. While this may sound like an advantage, hastened decomposition leaves the soil bare.
3. Contributes to Climate Change
Yes. I know this may sound far-fetched but there is indeed evidence that tillage farming contributes to climate change.
Tillage farming is machinery heavy. The usage of machinery in land preparation increases the output of greenhouse gasses. This is because most farming machinery is powered by fossil fuels.
A 2017 report showed that in the US no-tillage saved the use of about 588 million gallons of diesel. Apart from the reduction in diesel use, lack of machinery use saved 5.8 million tons of CO2 that could have been released into the atmosphere. In 2020 alone, agriculture accounted for 11% of greenhouse gas emissions.
4. Damages the Soil Structure
Another huge downside of tillage farming is the destruction of soil structure. Soil structure does not just involve how the layers are organized but also how individual soil particles are organized.
Healthy soil should have about 3-5% organic matter, 25% water, 25% air, and 45% minerals. On top of that living microorganisms.
The first way in which tillage affects soil structure is through compassion. The heavy machinery compacts the soil leaving no space for water and air. At the end of tilling, the soil is compacted and cannot absorb water, and has less air.
Tillage also contributes to the damage of soil structure by leaving the soil more prone to erosion. During tilling, most of the organic matter is buried deep exposing the soil to erosion agents. Tillage also hastens the decomposition of organic matter.
5. Poor Water Quality
One of the major downsides of tillage is erosion by either water, gravity, or wind. This does not end there. The eroded soil ends up in rivers, lakes, and other water bodies leading to water pollution. Erosion also leads to the transportation of phosphorus and nitrogen from the farms, which can lead to excessive algae growth. Excessive algae growth takes all the oxygen causing the death of other aquatic life.
Sedimentation by eroded soil also clogs waterways negatively affecting fish and other water life and also making it hard for light to penetrate.
6. Loss of carbon (C) from soils
Soil holds the most carbon compared to the carbon in the atmosphere, plants, and animals. However, soils are losing carbon adding to the total greenhouse gas emissions. Carbon is lost to the atmosphere then the soil carbon is exposed to oxygen.
Some of the causes of this exposure include tillage, fertilizers, and pesticide among others. Loss of carbon downgrades the ability of plants to provide nutrients.
7. Decreased Nitrogen in the Soil
One of the most important soil nutrients is nitrogen. Nitrogen is key in giving plants the green color and is also vital in photosynthesis. Soil gets nitrogen from organic matter and fertilizers. The issue with tillage is that it increases the loss of nitrogen from the soil.
Nitrogen is lost from the soil through erosion when tilled soil becomes weak and susceptible to erosion agents.
8. Tillage is costly and labor intensive.
Tillage machinery is very expensive and the cost of operations is equally high.
9. Tillage accelerates the evaporation of moisture from the soil.
What are the Important Benefits of Tilling Soil – You May also be interested in Reading this Article.
Tilling Alternatives – Conservation farming
As you can see, tillage farming has a lot of downsides. It destroys the soil structure, makes the soil more prone to erosion, and affects soil life.
But another big question is, is there an alternative to tillage farming, and are they effective?
Yes, there are several tillage farming alternatives. These conservation farming methods aim to keep soil disturbance to a minimum while ensuring high production
Types of conservation tillage
- No-till (zero tillage or direct drilling)
- Mulch tillage
- Strip or zonal tillage,
- Ridge till
- Minimum tillage
What is Conservation Tillage?
There are different types of conservation tillage such as no-till and minimum or reduced tillage. All these methods involve growing crops with the least soil disturbance. This type of tillage addresses most of the issues with tillage farming. For instance, most conservation tillage methods don’t disturb the soil structure and there is reduced erosion.
Advantages of Conservation Farming
- There is little or no soil erosion
- The soil structure remains intact
- Soil has better water retention and minimal evaporation
- Less release of greenhouse gasses
- Very little disturbance to the soil
- Cheaper since there is less use of inputs
- Lesser use of tilling machinery
- There are a lot of financial incentives for conservation tillage
- Less loss of nitrogen and carbon
- Better aeration and water penetration
Frequently Asked Questions about Disadvantages of Tillage
Can you over till a garden?
Yes. There are several ways that people over till land. First, tilling and plowing several times a year. While it may look beneficial, over-tilling is bad for the soil. First, over-tilling destroys the soil structure and disturbs the soil microorganisms.
Over-tilling also includes tilling very deep, when it’s not necessary, and over-preparing land. The soil surface will look neat but the soil won’t be healthy.
What is Excessive Tillage?
Excessive tillage is when tilling is done many times over a short period. For instance, plowing, harrowing, bed formation, and cultivation after each other. All these activities disturb the soil structure and microorganisms.
What’s Wrong with Tilling?
Tilling has so many downsides. First off, it disturbs the soil life. Secondly, it destroys the soil structure leaving the soil susceptible to erosion. Tilling also affects moisture retention abilities
What can I do instead of Tilling?
Several conservation farming methods are great alternatives to tillage. One is minimum or reduced tillage. This is a form of tillage that does very little disturbance to the soil.
No-till system of farming involves just a one-pass planting while leaving the soil residues intact. Other types of conservation tillage include:
- Mulch tillage
- Zonal tillage
- Minimum tillage
Does Tilling Lead to Erosion?
Yes, tilling land destroys the soil structure leaving soil particles loose and prone to erosion. Tilled land experiences higher water and wind erosion. Also, the soil is left bare, increasing the impact of raindrops.
How does Tillage affect Soil Organic Matter?
During tillage organic matter is distributed unevenly and buried deep, There is also increased decomposition and release of CO2 to the atmosphere. The accelerated decomposition leads to less stable humus.
How does Tillage Affect Soil Aeration?
Tillage improves soil erosion, which further accelerates the decomposition of organic matter leading to low-quality humus. Some areas are also overly compacted by the machinery during tilling negatively impacting the aeration.
How does Tillage Affect the Ecological System?
Tillage affects the ecological systems in different ways. First, tillage contributes to climate change because of the emission of greenhouse gasses. Secondly, tillage disturbs and destroys the soil microorganisms.
Does Tilling Release Carbon into the Air?
Yes, tilling accelerates the loss of carbon from the soil. Studies show that CO2 levels are the highest when farmers are preparing their land.
How Tilling is Killing the Atmosphere?
Studies show that tillage is contributing to climate change. Tilling contributes to carbon release from the soil. The machinery also releases greenhouse gasses
Why is No-Till Farming Better?
No-till and other conservation tillage methods have lesser impacts. For instance, there is less disturbance to the soil and less erosion. Other benefits include increased soil organic matter and less carbon and nitrogen loss.
How does no-till farming help in soil conservation?
No-tillage leads to improved water retention, less erosion, better retention of the organic matter, and less disturbance. All these benefits are key to soil conservation.
How does no-till farming reduce carbon emissions?
First, there is less use of fossil fuel-powered machinery and secondly, there is less carbon loss from the soil. This helps to reduce the greenhouse gas emissions that play a role in climate change.
Disadvantages of Tillage In Conclusion
Tillage is one of the oldest farming activities in the preparation of land. However, studies show tillage has very many downsides. They include soil erosion, destruction of soil structure, high C02 release, and soil disturbance. Different conservation tillage methods seek to solve these problems. Some of these methods include no-till and minimum tillage. While no-till farming is not easy, it is helpful to both the farmers and the world