This technology includes features of conservation agriculture, conservation tillage, conservation tillage equipment including the -hand-operated jab planter- and features of cover crops. All those practices are labour-saving technologies.

 Description

1. Features of conservation agriculture

Conservation agriculture is the simultaneous practice of permanent soil cover, minimal soil disturbance and crop rotations. This is achieved by:

• the maintenance of a permanent vegetative soil cover or mulch to protect the soil surface; direct planting without seedbed preparation through the soil cover to minimise the disturbance of the soil;
• crop residue management and weed control, to stimulate soil structure formation, improve soil fertility, and to control weeds (with dependence on herbicides); and
• disease control based on Integrated Pest Management, crop rotations and inter-cropping.

Inputs include cover crops, the use of draught animal-powered knife rollers or herbicides to crush or kill weeds and cover crops, and no-till planters. Farmers require extensive training and change in mindset to shift from traditional practices to conservation agriculture.

No-tillage practices are suited to areas with high rainfall (> 1 000 mm to ensure high levels of biomass production and minimum competition from livestock for crop residues), long growing period (more than six to seven months for biomass production), soils with more than 20 percent clay content (to reduce risk of soil compaction).

Minimum tillage, rather than no-tillage systems are considered to be more appropriate in semi-arid and arid regions with 300 mm to 800 mm annual rainfall.

Conservation agriculture is suitable in areas where there is a capacity to grow cash crops (in order to purchase inputs), markets for a diverse range of crops (to support crop rotation), secure access to land and limited value on crop residues (as livestock fodder and firewood).

It is possible to adopt components of conservation agriculture in a piecemeal manner: for example, inter-cropping cover crops or using conservation tillage equipment or herbicides. These components may act as entry points for moving towards full conservation agriculture.

2. Features of conservation tillage

There is a range of tillage operations that reduces the losses of soil and water, in comparison to conventional tillage, including (in order of reduced soil disturbance):

• reduced tillage
• semi-permanent planting basins
• ridge tillage
• tined tillage
• strip tillage
• zero tillage. 

2.1 Reduced tillage

Tilling the whole surface but eliminating one or more of the conventional tillage operations.

2.2 Semi-permanent planting basins

Known as tassa in Mali, zai in Burkino Faso, demi-lune in Niger, potholing in Zambia, the Matengo pit system in Tanzania.

2.3 Ridge tillage

A system of annual or semi-permanent ridges and furrows, resulting in some residue cover.

2.4 Tined tillage

The land is prepared with implements that do not invert the soil and which cause little compaction, resulting in a good cover of residues on the surface in excess of 30 percent. Equipment used includes chisel plough, vibro-cultivator and draught animal-powered ripper.

2.5 Strip tillage

Strips 5 cm to 20 cm wide are prepared to receive the seed and the intervening bands are not disturbed.

2.6 Zero tillage (or no tillage)

Planting the seed into the stubble of the previous crop without any tillage or soil disturbance. Weed control relies heavily on herbicides. This approach is broadly equivalent to conservation agriculture.

Sub-soiling may be necessary before switching to conservation agriculture to remove hardpans caused by years of hand hoeing or ploughing.

Plough pans are broken up using use ripper tine with draught animals or tractors at the end of the cropping season when the draught animals are in peak condition and before soil hardness increases during the dry season. Alternatively, where time allows, cowpeas may be planted to break up the hard pans.

Excessively uneven land that could lead to waterlogging (possibly resulting from previous poor ploughing practices) are corrected using damscoops or levellers with draught animals or tractors at the end of the cropping season before switching to conservation agriculture.

3. Conservation tillage equipment

3.1 Hand-operated jab planter

The hand-operated jap planter plants through crop residues and crop cover with no tillage and removes the need to prepare the land for planting. It can also be used to apply fertilizer.

3.2 Knife roller drawn by draught animals

The knife roller bends over and crushes crop residues and cover crops prior to planting which then remains on the field as soil cover), saves the removal of crop residues by hand and acts as a cover to suppress weeds.

3.3 Draught animal-powered ripper

The draught animal-powered ripper allows for planting strips in reduced tillage systems by cutting furrows rather than inverting the soil.

A planter attachment places seed directly in ripper furrow. Wings can be attached for ridging and weeding which reduces time by half because do both sides of the row in one pass.

3.4 Draught animal-powered seeder/no-till planter

This equipment helps to plant directly through the cover crop: plant through crop residue and crop cover with no tillage and removes the need to prepare the land for planting.

4. Features of cover crops

• A cover crop is any crop grown to provide soil cover, regardless of whether it is later incorporated into the soil.
• Cover crops and green manures can be annual, biennial or perennial herbaceous plants grown in a pure or mixed stand during all or part of the year.
• They are grown primarily to prevent soil erosion but they also reduce soil surface temperature and water losses, add organic matter to the soil, stimulate soil life, suppress weeds and some fix nitrogen. Examples include dolicos lablab and mucuna.
• Weed, disease and pest problems need to be addressed before switching to conservation agriculture.

Figure 1. Labour-saving technologies and practices: conservation agriculture

©FAO/TECA

5. Advantages and disadvantages of conservation agriculture

5.1 Advantages

5.1.1 Labour saving

• Reduced labour inputs for land preparation and weeding once the system becomes established;
• more even distribution of labour across the year;
• more timely operations; and
• a reduction in drudgery.

Changes in draught animal power systems from the mouldboard plough to shallow ripping saves labour.

5.1.2 Livelihood's resilience strengthening

• Represents a move towards a more sustainable farming system with increased yields.
• The quality of the environment is improved and the previous degradation reversed.

5.1.3 Livelihood diversification

• More time is available to undertake off-farm work and hire out services (for example, draught animals).
• There is the opportunity to move into growing organic produce with payment premiums.

5.1.4 Cost

• Reduced requirement for herbicides and fertilisers once the system established.

5.1.5 Risk

• There is a risk in changing land over to conservation agriculture gradually (one plot at a time) in order to minimise risk of using a new farming system.

5.1.6 Agro system’s resilience increased

• Livelihoods and the agro system are benefited in a way that they are more resilient to adverse weather events and variability.

5.2 Disadvantages

5.2.1 Labour

• Additional labour inputs are required initially whilst establishing a system for the application of lime, farmyard manure, weeding, breaking hand pans and constructing planting basins.
• Manual and draught animal-powered minimum tillage systems (without cover crops) increase labour requirements for weeding because they do not bury weeds by inverting the soil during land preparation.
• An initial investment of time and energy to construct some of the reduced tillage systems is required.

5.2.2 Attitude

• Other farmers may regard the retention of cover crops and crop residues as a lazy form of farming.

5.2.3 Equipment

• More complex draught animal-drawn equipment requires skilled local manufacture or import.
• Farmers require access to seeds of green manure/cover crops, herbicides, liming or farmyard manure to adjust the soil acidity, and fertilisers when crop residues are left on the field until a new equilibrium is reached.

5.2.4 Cost

• The cost incurred is the purchase of conservation tillage equipment and herbicides.

5.2.5 Skills

• Farmers need extensive training and changes in the approach to conventional farming systems.

5.2.6 Risk

• The ability to grow the cover crops is compromised by:
  • the strong demand for crop residues as forage for livestock; in addition, 
  • the communal land tenure system limits the right of land use to the growing season.
• Higher levels of surface trash may result in higher plant disease and pest infestations, if not managed properly.
• The system not suited to low precipitation, short growing season, sandy soils and soils at risk of waterlogging.

5.2.7 Infrastructure

• Access to appropriate inputs and skilled extension service might be constrained.

6. Related/associated technologies

• Labour-saving technologies and practices: improved hand tools for harvesting cereals: ID 7295.
• Labour-saving technologies and practices: improved use of hoes for land preparation, planting and weeding: ID 7296.
• Labour-saving technologies and practices: integrated pest management: ID 7298.
• Labour-saving technologies and practices: raised beds: ID 7299.
• Labour-saving technologies and practices: row planting, hand seeders and planters: ID 7301.
• Labour-saving technologies and practices: seeds and crops: ID 7302.
• Labour-saving technologies and practices: weed wipes and knapsack sprayers: ID 7303.
• Crop rotation in conservation agriculture: ID 7415.
• Introduction to conservation agriculture: its principles and benefits: ID 7413.
• Green manure/cover crops and crop rotation in conservation agriculture on small farms: ID 7250.
• Conservation agriculture for smallholder farmers in dryland areas: ID 4676.

This technology is also available in Spanish: ID 8684.

7. Objectives fulfilled by the project

7.1 Labour-saving technology (LST)

This technology saves labour once the conservation agriculture system is established due to the reduced quantity of labour required to undertake the regular farming tasks. 

7.2 Resource use efficiency

This technology is lower in costs and inputs due to the no-tillage system, and the reduction in the quantity of herbicides and fertilizers required. 

7.3 Pro-poor technology

Due to enhanced livelihoods resilience and resistance, and the reduction in the operational costs of the system, this technology is considered an economic and sustainable practice in the long run. 

8. Further reading

• FAO. Conservation agriculture (CA) Addressing women's work burden: key issues, promising solutions and way forward".