The primary objectives of tillage in any cropping system are to control weeds, enhance soil water storage and retention, reduce erosion, as well as prepare a desirable seedbed. Unfortunately the method used to achieve any one of the above objectives may produce a conflict with other objectives, and also with other practices in the farming system. For example, conventional tillage practices used in many areas today rely on numerous, repeated cultivation to control weeds or to form a soil mulch to reduce evaporation. But as the number of tillage operations is increased, the degree of soil aggregation is decreased providing greater risk of erosion. Each additional tillage operation for weed control also buries more crop residues and exposes moist soil to the surface, causing additional water loss. 

In Uganda 17 million hectares of the total land area are classified as arable land. Out of this, only 4.6 million ha (27%) are currently under cultivation (Agricultural sector Memorandum, 1993). Traditional tillage operations include use of the hand hoe, ox-plough or tractor for opening up of land. For almost all the other subsequent operations, the hand hoe is predominantly used. In many cases the traditional tillage practices are not conducive to the above noble objectives of proper tillage. The above examples all point to the need for better integration of management methods to achieve proper tillage objective. 
  

Conservation Tillage Systems 

Conservation tillage is a concept of farming designed to minimize tillage operations and thereby reduce energy requirements. The aim is to maintain adequate weed control and maximum residue cover for protecting soil against erosion, and increasing water infiltration, without reducing crop yields. Conservation tillage practices have the potential for increasing yields because of increase in stored soil water which is almost always the critical factor in crop growth especially in dryland production. Conservation tillage also minimises labour, energy, and capital. The practice may range from a few tillage operations for weed control and seedbed preparation to one-pass no-tillage planting, and excludes conventional ploughing and other intensive soil inversion cultivation systems; although that may also be the minimum required in exceptional circumstances. Terminology such as plant till, strip tillage, mulch tillage, sod planting, minimum tillage, stubble-mulch tillage, and more recently, no-till, low till, zero till, chemical fallow, ecofallow and conservation production systems are all used to describe practices related to, and included within the concept of, conservation tillage. 

Conservation tillage has great potential benefits in the semiarid regions where rainfall is erratic and soils are highly variable and subject to wind and water erosion. Maintaining vegetative cover on the soil surface is the simplest way of controlling wind and water erosion. With proper management, more surface residues are retained which will reduce runoff, sediment loss, air pollution, and protect surface soils from wind erosion. Without surface residues, tillage is frequently needed after a rain to break the soil surface crust, to control wind erosion, or to facilitate seedling emergence. 

Typical conservation tillage operations in Uganda are employed in the growing of several traditional crops. In the case of cassava for example, the practice by smallholder farmers is to slash the field to lower the height of the grass. Holes are then dug at appropriate spots into which cassava cuttings are planted. The residue from the slashed grass acts as mulch to reduce water loss as well as loss of the soil through rain, water and wind. Similarly in grain crops such as maize and beans, a chisel plough is used to scratch dry soil surface after slashing the grass and the seed planted there on. The grass cover, likewise protects the loss of moisture and soil as in the case described above. When the rainy season starts, the crop so planted will have a head start on any weeds that may complete with it. Such typical conservation tillage operations are employed for crops especially in drier areas of the country. 
 

Soil and Water Conservation 

In the past mainly physical (terraces, bunds & basins) and biological (tree planting, rotational grazing and protected areas) measures designed to control/minimise run-off were being encouraged by the colonial administration. Later the agronomic measures (crop rotation, early land preparation & planting, proper spacing, early weeding, disease & pest control, fodder cropping etc.) were added to the above package and were included in the extension service. Bye laws were enacted to enforce their implementation by the district authorities and extension service. 

In Uganda, most of these measures have become „indigenous", while others were rejected or not maintained because they didn’t seem to address the farmers’ immediate socio-economic felt needs (increased food and income) and/or were too labour intensive. 

Emphasis has been on stopping soil erosion and its off-site effects leading to land degradation. Conservation was characterised by an engineering approach and often featured the use of heavy machinery to construct the physical soil conservation structures. The types and causes of land degradation experienced in Uganda and the districts/areas affected most, are given in Annex 1. The causes are mainly a result of man’s accelerated interventions with the environment to produce food and to derive other social economic benefits. 
 

Approaches to Soil and Water Conservation 

There have been several approaches to address different issues on soil and water conservation in the Ministry of Agriculture, Animal Industry and Fisheries, (MAAIF) in Uganda. Some of the approaches include: 

• Land-use-planning was introduced as a way of matching land use with its capability. This was done with little farmers’ participation.
• Soil & water conservation and land tenure systems was formed later under the land planning service unit. Still emphasis was on stopping erosion.
• Irrigation services were formed under Land Planning Service.
• Farm Management was also formed under Land Planning services to assist the farmers keep records of their transactions and practice farming as a business but still with top-down approach.

All the above approaches were treated as separate advisory services, targeting the same client and using a clear top-down approach. Besides, there were also commodity/project approaches viz.; tea, cocoa, coffee, cotton, cashewnuts, dairy husbandry, pastures/ranch management, tobacco, horticulture etc. 

In the 1970s the Farming Systems and Land use planning was formed under Land Planning unit to study the ecological zones, client, plant and animal bio-diversity etc. In the Late 1980s to early 1990s Agro-forestry which includes animals, crops and trees growing together as a way of farming was considered and introduced under the soil and water conservation section. 

Currently in the offering is a country programme on Land Management which has been proposed by Ministry of Agriculture, Animal Industry and Fisheries (MAAIF) and is to be funded by Sida. In 1992 a pilot project on the same was initiated in Mbarara district. An appraisal is being carried out to expand the programme to include the districts of Arua, Kabarole and Kapchorwa. 
 

Technologies available in Uganda 

As mentioned above, the approach has been top-down with little or no farmer participation. The emphasis now is more on using a bottom-up approach with more participation of the stakeholders in identification, planning, monitoring and evaluation of activities all geared towards improved productivity and conservation of resources. 

The technologies outlined below are mainly biological, agronomic and physical measures integrated in the farming systems as well as encouraged by intervention of aid agencies and our extension services. Their applicability depends on decision reached by all stakeholders depending on the terrain, rainfall, affordability, knowledge and skills to implement available technology. 

Biological/Cultural Measures (agronomic practices) 

• Contour ploughing and planting
• Timely planting and weeding
• Optimum plant population (correct spacing)
• Crop rotation
• Trash lines along contours etc.
• Inter-`cropping, mixed cropping and agro-forestry
• Wind brakes
• Mulching
• Optimum stocking rates
• Grass strip
• Organic farming (green manure, farm yard manure, composites, liquid manures, organocides, etc.)

 Physical/Structural Measures 

• Terrace, bench and channels
• Cut-off drains
• Retention ditches
• Artificial water ways
• Check dams (wooden, vegetation, stones etc.)
• Semi circular water loops (water harvesting)
• Valley dams and tanks.

Constraints 

Constraints encountered in conservation tillage include: 

• Costs, labour and time required to practice a given soil and water conservation methodology as well as erect the available soil & water conservation structures.
• El nino causing too much rain thus washing off soil & water conservation structures. El nino also results into unexpected droughts with speedy winds.
• Lack of technology adoption by inhabitants of the water catchment (for example you can not effectively practice soil and water conservation and yet your neighbour upstream or downstream does not).
• Varying degrees of emphasis on soil and water conservation policies and measures in Uganda.
• Lack of local funding to conservation tillage programmes.
• Poor staffing at the front-line level.
• Land tenure systems making land accessibility, ownership and development difficult.
• Inconsistent research programmes, hence slow flow of new technologies and messages into extension services.
• Poor transfer of technologies.

Opportunities 

Outlined below are opportunities for further development on conservation tillage. 

• The country has decentralised agricultural extension services to districts trying to establish a bottom-up approach, which is in line with the government policy. Agricultural Officers are now to man and over see all agricultural services at subcounty level with a view to improving on household food security and incomes. This will strengthen Research- Extension-Farmer linkage.
• Strengthening Research and Development with information and technologies. R&D has for a long time been crop production oriented. There is need to tackle the environmental protection and resource conservation aspects and aspects like soil fertility or water harvesting.
• With the present government policy of provision of water for production services, there is need for interventions to develop water harvesting and conservation techniques including irrigation.
• With the Land reform bill in progress ownership rights in the land tenure systems will be well defined. As a result land use improvement difficulties will be tackled and eliminated. Thus enabling beneficiaries to develop their farm land holdings.

Key Features related to the Farmesa Field Sites 

Overview 

The two field sites of Farmesa programme in Uganda fall in the two districts of Mukono and Kumi. 

Mukono District 

Is located in the central and northern shores of Lake Victoria Crescent region of Uganda at an altitude of between 1,200 and 1,500 metres. It has a mean annual rainfall between 1,250 - 1,500 mm, with average maximum temperature of 27 to 30 degrees centigrade. Approximate district area is 14,242 sq. km, of these forest cover is 590 sq. km. Total arable land is estimated at 4,149 sq. km. According to 1991 census, the total district population was 824,604 people. This works out to average density of 199 per sq. km or 0.5 acres per person. The soils are mainly sandy clay loam with a natural vegetation of forest savannah with elephant grass and forest remains. 

Kumi district 

On the other hand is located in the north eastern part of Uganda at an altitude of between 760 and 900 meter with average annual rainfall of between 1,000 and 1,200 mm. In addition to being less plentiful, rainfall in Kumi is more concentrated over a shorter period, with onset of the main rains coming later, leaving a longer dry period from December to February or March. The district has a total land area of about 2,861 sq. km of which 2,857 sq. km is arable. Based on the 1991 census, the population of the district was 237,000 with an estimated 52,599 households engaged in agriculture. From these figure the district mean land holding per person is 1.2 ha. The soils are generally lighter and poorer, being mainly sandy sediments with some sand loams. Natural vegetation was chrysopogongrass steppes (short). 
 

Agro-ecological zones and Farming Systems 

Mukono District is in the Southern and Western tall-grassland agro-ecological zone (tall-grassland area producing perennial and annual crops in mixed farming) with Banana-Coffee mixed Farming Systems. It was in the past scheduled for the valuable cash crop of robusta coffee and individuals have also taken advantage of other income generating opportunities, of which the most recent is vanilla. Exotic livestock were introduced early on. The main crops grown in the district include: bananas, coffee, cassava, beans, sweet potatoes, maize, a variety of horticultural crops and vanilla. Major livestock include: cattle (locals, crosses, friesians), goats, sheep, pigs and poultry (local chicken, broilers, layers etc.) 

Kumi District lies in the Northern and Eastern Short-grasslands agro-ecological zone with Cotton-Finger millet mixed Farming Systems. Kumi was largely pastoral, with cattle and small ruminants being mainstays of the farm economy, which placed further pressure on the land there. In addition the main cash crop was the lower value, labour intensive, high risk cotton, while the staple food of millet was unimproved and low yielding. Repeated uncontrolled cattle raiding from Karamoja in the early 1980s was followed by the insurrection in the years 1986 - 1991 which left the rural economy in ruins and wiped earlier advances. Most particularly it has deprived farmers of their major resource of cattle and oxen, which were of vital importance culturally and economically. 

The main crops grown in the district include: finger millet, sorghum, cassava, sweet potatoes, cow peas and green grams while the major livestock are cattle, goats, sheep and poultry (turkey, local chicken). Cotton used the to be the major cash crop, however it suffered a drastic decline over the last two decades due to the collapse of government input supply and extension programmes. 
 

Issues of land tenure. 

Land is a fundamental resource, not only the quantity and quality available to the individuals cultivators is important but the conditions/laws under which it is held and used. 

Mukono has a „Mailo Land" tenure system. The Mailo land has freehold status and the owners, who are few have been able to sell or lease their land to others by transferring the freehold title or by lease for a certain period of time. This has rendered most peasant farmers as tenants of the Mailo owners, and some household are squatters. Several community members acknowledge that they have restricted access to excessive land in Mukono. 

In contrast to Mukono Mailo land tenure system, in Kumi, land ownership is still derived from inheritance. There is no land market but only the customary freehold of land thus making access to large acres of land restricted in Kumi. 

The system of land ownership in Uganda is presently undergoing review. Under the 1996 Constitution, a comprehensive land law is being formulated and is expected to be enacted upon soon. The current situation is regulated by the Land Act of 1969 and 1974 neither of which was adequately supported by further enabling legislation. 

At present there are several different categories of land: Public land owned by the Government and land assigned in the past to religious missions; Mailo land; and „Bibanja" (land acquired by tenants from Mailo owners), that is held, inherited, and even rented under various forms of traditional tenure but without legal tittle. 

During the 1960s the category of Bibanja was also officially abolished and land formally became public property. This abolition has little practical effects as people continued to operate under whatever their particular traditions had been. However, it is possible to obtain a 49-year leasehold tittles for development purposes, such leasehold tittle being used as security for loans, only those interested in development seek to obtain the leases. 
  

Available Tillage practices 

Mukono District. 

• Mulching with crop residues, weeds, and live crops (cover crops) in perennials, (banana, coffee), horticulture (vegetables, flowers, fruits)
• Mixed farming systems with crops, trees and pastures (elephant grass on conservation structures)
• Mixed cropping, bananas, cocoyams, yams pumpkins beans etc to utilise the upper and horizontal space.
• Early land preparation before rains
• Early planting before or immediately after onset of rains.
• Close spacing as a result of mixed or inter-cropping (maize/beans)
• Improved seeds with proper spacing, proper germination and coverage.
• Contour cropping especially on sloping land.
• Retention ditches, holes and channels in bananas, coffee, citrus and vegetables
• Vegetation buffers and fodder crops.
• Ridging; for sweet potatoes, swampy sites etc.
• Farm yard manuring from zero grazing animals.
• Planting pits in bananas, coffee, etc plus composting.

Kumi district 

• Grass strip of 0.5 - 1 metres width enclosing land of approximately 1 acre (0.4 ha) following contours after every 40 - 50 metres from preceding strip.
• Crop rotation e.g. cotton - millet - groundnuts/cow peas then sweet potatoes and cassava
• Early land preparation.
• Improved seed/variety which germinate well and cover ground quickly.
• Proper spacing giving good coverage
• Early planting and weeding
• Mixed farming, where livestock graze on crop stover (residues)
• Dry planting, of millet before rains giving ground cover quickly after rains.

• Potential for Conservation Tillage in the Farmesa field sites
• Because of heavy, sporadic and short lived rains during the wet season coupled with high speed winds during the dry season, there is an urgent need to protect soil and conserve water.
• Improve on the indigenous conservation tillage methods mentioned above.
• Improve and empower local extension services network (front-line extension staff)
• Strengthen the use of farmer groups to develop, disseminate and use skills and knowledge in soil and water conservation.
• Strengthen collaboration with the interested NGOs. and other stakeholders.
• Need to improve on the fertility of the soils which are low as of now.

Need for further Information and Action 

• The soil fertility data recently carried out in central Uganda indicate that our soils have low levels Organic matter, phosphorus, Magnesium, Sodium and pH. There is need to update data on fertility levels of our land resources especially on the Farmesa field sites. Land degradation has been accelerated over the years and fertility levels have tremendously.
• Available conservation tillage practices do not show their origin, importance and socio-economic impact in the farming systems. There is need for information on conservation tillage through Participatory Rural Appraisal (PRA) then Research and Development.
• There are other stakeholders working in the two districts of Mukono and Kumi on Agro-related activities. However in terms of conservation tillage; coverage, beneficiaries, data etc. are not known. There is need to find out who the stakeholders are and what they are exactly doing.
• Since there are many tillage objectives in any cropping system, there is agent need for better integration of management methods to achieve a self sustaining farming system.

References 

Annex 1 
 

Research Engineer, Agricultural Engineering and Appropriate Technology Research Institute, P. O. Box 7144, Kampala, Uganda.