ABC of NO-TILLAGE practices

July 2020

Gavin Mathews, Bachelors in Environmental Management. Send an email to gavmat@gmail.com

No-till is a system of conservation tillage which aims to conserve soil and moisture. This practice has become a common method used by farmers, especially in the higher rainfall areas of South Africa.

Many of the advantages that can be achieved by employing no-till methods are often only achieved after a number of years of practice, thus one should have a long-term outlook when starting. There are also key ‘rules’ which farmers need to focus on to get the best possible results. Sustainability is the key! We want future generations to be able to produce food just as we do, and in order to achieve this there still needs to be topsoil left for them to produce crops on.

PRIMARY PHILOSOPHY
No-till practices aim to have minimum disturbance on the soil structure. Rather than turning the soil over to create a seed bed, farmers focus on building a layer of mulched organic material on the top of the soil in which to plant crops. This layer of material can aid in reducing loss of topsoil and achieve better infiltration of moisture by reducing run-off.

Another advantage of having the top layer of soil covered is that weed growth is suppressed and microbial development can occur. All of these factors can contribute to the sustainability of the soil. 

Profit is obviously another big consideration when making the move to no-till. Many farmers make the mistake of thinking that no-till will be an easy quick saving on production costs. One would assume that less tilling equals less tractor use, therefore a big saving on diesel. This is unfortunately not the case, at least not in the short term. Research has shown that during the ‘building’ phase of no-till one can expect slightly lower yields than usual as one works toward achieving that all important layer of stubble material and while the soil structure establishes itself. Always bear in mind that a long-term approach is needed when implementing no-till practices.

EQUIPMENT
Having the correct equipment is vital to successful implementation of no-till. You need to have a planter which is suitable to plant under no-till conditions. This would usually consist of a planter that can give significant downward pressure to penetrate through the top layer of material and crust. A drawbar hydraulic system is preferred over a three-point connected planter.

The planter should also be equipped with a ripper tine and cutting disc that can break through the material, some planters also make use of a trash wheel which is an angled tine wheel that ‘sweeps’ the trash away making it easier for the planting discs to penetrate the soil.

Your planter should also have good sharp coulters that can cut the groove into the soil where the seed will drop into followed by compaction wheels that squeeze the opening closed. Another essential piece of equipment that you will need is a good spray rig. Considering that you will not be doing conventional mechanical weed control with a cultivator you will need to be sure that your boom spray is in an excellent condition to do chemical applications to control weeds.

If you are considering moving to a no-till system, it is highly recommended that you make use of the correct equipment for the job. One should look at this as investment into a system that can be advantageous into the future.

INITIAL STARTING POINT
You need to have a good starting point from which to build. Don’t start a no-till programme on a bare piece of land that hasn’t been worked for many years. One should rather have a well worked field that is not compacted and overgrown by weeds on which to start building. This may require you to do one good conventional working of the soil in the first year.

After your land is prepared and ready to be planted you should now consider what crop to plant. Think about the material that you aim to start building-up on the land and what best will provide you with the most bulk to give good soil coverage. For example, maize would be a better option compared to sunflower as the stalks and leaves have better structure and volume than sunflowers.

After harvesting your crop, it may be a good option to spread a winter cover crop on the field such as oats or wheat. This will help to provide soil cover and structure and will also assist with the building of a material stubble layer on your topsoil. When it comes to the next planting season you will have a good foundation to work on. Make sure that you do a ‘burn down’ spray early in the new season to prevent the weeds from getting too established. Once all weeds are controlled you can plant into your previous season’s stubble and cover crop and start your building process.

GOAL
Remember that this is a long-term programme that will only start to pay dividends after a few years of implementation. Keep the end goal in mind – sustainability! Keep working towards building those layers and developing your soil structure. Keep learning and don’t be afraid to ask for advice from experienced no-till farmers.

Publication: July 2020

Section: Pula/Imvula