IMPROVE YOUR SOIL BY PRACTISING ZERO TILLAGE

For many years now, farmers have practised tillage at the start of every season and inbetween the growing season with the hope of removing weeds, shaping the soil into row and farrows for irrigation and creating a fine seed bed thus improving seed germination.The loosened soil also tend to provide a more favorable rooting environment, facilitating seedling survival and plant growth.

This tillage system was first practised primarily in the western part of asia,europe and north america with all the said advantages above in mind. In addition,At the end of the growing season, the entire crop was harvested, because the straw also had considerable economic value for animal bedding, roofing thatch, brick making, and fuel. Although this cropping system lasted for centuries, it resulted in excessive erosion, especially in the Mediterranean region, where it caused extensive soil degradation. Eventually deserts spread as the climate became drier.Tillage history
Often the experts have spread the concept that tillage makes the soil fertile and therefore its okay to practise it. They have not however understood the significance of soil erosion, as well as intensive weathering under hot, humid conditions. This has resulted in the widespread distribution of poor, badly eroded, infertile soils all over the tropics and subtropics.

What you loose by excessive tillage.

• Organic matter and crop residues are quickly decomposed, with a downward trend in soil organic matter
• Loss of continuous root canals and macropores reduces rainwater infiltration
• Erosion is multiplied tenfold
• Greater drought susceptibility
• Sterilization of the soil life - especially mesofauna and micro-organisms
• Buried weed seeds are brought to the surfaceAdditional costs of soil preparation and re-making contour banks
• Delays in planting
• Higher level of investment in machinery

Zero tillage

The idea of modern no-till/zero tillage farming started in the 1940s with Edward H. Faulkner, But the development of several chemicals after WWII led to various researchers and farmers starting to try out the idea( Wikipedia) . In general, zero tillage is considered a way of growing crops or pasture from year to year without disturbing the soil through tillage.

Effective zero tillage

Zero tillage farming requires some different skills to achieve success. As with any production system, if no-till isn't done correctly, yields can drop. A combination of technique, equipment, crop rotation, fertilization, and irrigation have to be used for local conditions. For an effective zero tillage, consider this pre-conditions for adopting zero tillage as put forward by FAO .Here, its recommended that Both the farmer and his workers should have a thorough understanding of the new technology. This implies training and observation of practicing farmers. A farmer should consider doing the following;

1. Correction of soil chemical and physical properties limiting maximum plant growth, especially low lime and nutrient status, and hardpans.
2. Gradual and planned adoption over several years, choosing the most favourable fields first and correcting the limitations of the others.
3. A planter or seed drill specifically adapted for zero tillage, or a new specialized model must be available.
4. First planting in an easy situation and on less than 10% of total area. Second crop planting into soybean residue is recommended.
5. Avoidance of areas with troublesome perennial weeds. These should be brought under control first.
6. Re-alignment of roads, ditches or contour banks before adoption, if necessary.Availability of technical assistance, even if only from an experienced neighbour.

Expertly done zero tillage.(photo credits;washington post)

Advantages of zero tillage

• There is Improved soil structure, usually, tillage disrupts the natural structure of soil and releases some of the carbon soil organisms thrive on.  
• Soil biology plays an important role in providing crops with the water and nutrients they need.
• The danger for erosion is reduced by leaving more residue on the surface in the months when there are no crops growing.  Residue allows for rainwater to infiltrate the soil rather than causing surface run off that will carry away topsoil and nutrients. 
• Zero till farming can improve carbon sequestration process through the storage of soil organic matter in the soil of crop fields.When soil is tilled by machinery, the soil layers invert, air mixes in, and soil microbial activity dramatically increases over baseline levels. Tilling results in soil organic matter being broken down much more rapidly, and carbon is lost from the soil into the atmosphere. Also when tilling is done, emissions from the farm tractors increases carbon dioxide levels in the atmosphere.
• In Zero tillage, the soil is left intact and crop residue is left on the field. Therefore, soil layers, and in turn soil micro-organisms, are conserved in their natural state. This fields often have more beneficial insects, a higher microbial content, and a greater amount of soil organic material. Since there is no ploughing there is less airborne dust. Besides this, the crop residues on top of the soil provide food and shelter for small animals.

challenges to zero tillage

• Drainage; incase your soil has poor drainage, it may need drainage strategies in order to help with the removal of excess water under no-till. Farmers should thus remember that water infiltration will improve after several years of a field being in no-till farming, so they may want to wait until a recommended time of about 5–8 years to see if the problems persists before deciding to invest in any expensive drainage system.
• Crop rotation; If the crop rotation is not adequate, then their is a risk of some diseases remaining in the crop residues. The amount of perennial weeds can also increase, increasing the need for chemical weed control. However, there are many agroecological alternatives to increased chemical use, such as use of cover crops and mulch cover, soil solarization or burning.
• Equipments; Zero tillage may require specialized seeding equipment designed to plant seeds into undisturbed crop residues and soil. seed drills for example would be expensive and This would result in more money being invested into equipment in the short term.
• It takes time; to see the benefits of no-till, One can’t take a farm that has been tilled for 30 years or more and hope to see big gains in yield after one season.  Patience is important.  Soil needs time to regain structure, to increase the amount of organisms in the soil for its maximum and improved production.

Generally, like any other new venture a farmer may attempt to take up,it would require that the farmer,does a thorough research and get the knowledge and experince of the farmers who already ventured into it for easier transition.