Impact of Improved Fallows

An impact assessment workshop grouping farmers, extensionists and researchers was organised on 24 August 1999 in one of ICRAF’s pilot villages Abondo (see also 3.3.2). The main objectives of the workshop were to: (1) obtain farmers' views on the impact of improved fallows on their field, in their household, in their village and how to measure this impact; (2) elicit farmer expectations of magnitudes of impact and constraints in achieving these levels; (3) identify recommendation domains for improved fallows; and (4) identify factors affecting diffusion and adoption, and obtain suggestions for an action plan for dissemination of improved fallows.

The impacts of improved fallows were examined at three levels: farmers’ fields, their households and the village as a whole. Farmers generally found it easier to assess the impact of improved fallows on their fields than at household and village level. For example, in the working groups on impact at village level, participants often referred to the field level.

Impacts at Field Level

The results from the field level discussions are found in Tables 5-10 and 5-11. Farmers especially stressed effects of cajanus and calliandra on soil fertility and crop yields. Calliandra was said to increase the quantity and quality (healthier, bigger) of maize and cassava, provided that trees are well established, tree spacing is adequate and pruning regime respects research recommendations. Cajanus has moderately positive effects on maize, cassava and tomato and to a lesser extent on groundnut. Yield increases are monitored by number of bags or buckets harvested. The group working on impact of cajanus emphasised the need for a control plot to measure changes in soil fertility or crop yields. However, in case comparison with a control plot is not possible, other indicators for soil fertility are the amount of litter under the trees, the colour of the soil (soils under improved fallow are black) and increased activity of soil fauna such as earthworms.

Both calliandra and cajanus fallows reduce the amount of weeds in the field. The magnitude of this impact depends on the ability of the trees and shrubs to cover the soil rapidly and the amount of mulch produced. Nevertheless, participants expected no change from cajanus on frequency of weeding, but a moderate reduction of weed density, which facilitates the weeding task. The participants appreciated reduction of soil erosion by tree hedges, but it was considered less important because most of the farmers in the group crop on rather flat land. Another field level impact of cajanus is decrease in crop pests and diseases, which was attributed to a richer, thus healthier soil.

Impacts at Household Level

Many impacts were noted at household level, but they all more or less related to increased crop yields. Increased crop yields generate physical surpluses in addition to what is needed for home consumption. These surpluses can be sold and generate income. Moreover, calliandra trees, in addition to improving soil fertility, are used for stakes, fuelwood, bee

keeping and fodder, thereby diversifying farmers’ income-generating activities and thus, household income. The revenues coming from crop surpluses and other activities are used for health care and enable farmers to send their children to school, improving the general well-being of the household.

Calliandra fallows reduce the traditional fallow period considerably, which is interesting to older farmers who no longer have the strength to cut secondary forest or long fallow vegetation (> 10 years). The main constraint farmers face in the use of calliandra fallows and the development of related enterprises is organising these activities in time and space. Farmers already have many different activities and the integration of new ones requires a certain re-allocation of inputs (labour and other resources) at the household level.

The impact of the use of cajanus at the household level is also felt in higher yields, leading to increased income. Ripe cajanus seeds can substitute for groundnut whereas green seeds and pods can be eaten as a vegetable in many different forms (Duke, 1983). Seeds also constitute a direct source of income as they can be sold in local markets. According to the participants, a great advantage of cajanus is that it helps rural households to maintain continuous and sustained crop yields. The impact of cajanus fallows on labour demand (especially for slashing the cajanus shrubs after fallow) differs according to the ecological zone and prevalent cropping system. In fact, in the forest zone, cajanus fallows are an alternative to the traditionally practiced 4-year natural fallow, which consists of a lot of biomass. It is thus understandable that here farmers prefer cajanus to natural fallow because it is easier to cut. On the other hand, natural fallows in the humid savannah generally do not exceed 6 months and are mainly composed of grasses. Cutting cajanus in this environment is harder than clearing the natural grass fallow. According to the farmers however, integration of cajanus in the cropping cycle does not change the distribution of tasks within the household.

Impact at Village Level

In general, participants agreed that the use of improved fallows can enhance the well-being in the village, through increased crop yields, shorter fallow periods, less erosion and fewer weeds, provided there is a market for the crops grown. On the other hand, the introduction of calliandra in the village also raised some conflicts between farmers who adopted the technology and those who did not. For example, if calliandra is left to flower and seed without attention, calliandra seeds can spread to neighbouring farms. But participants noted that pruning trees close to neighbouring farms before they seed and/or collecting seeds before the pods open can avoid this type of problem. Many participants also thought that, through sensitisation and information, the whole village could understand the advantages of the innovation and become involved in improved fallows.

It was anticipated that the participatory approach of research and development of improved fallows in pilot villages would have strengthened the collaboration between farmers. However, ideas on this topic were divided. While some participants believed that collaboration between farmers within the village and between villages had improved, others

result of the introduction of improved fallows, members of the group abandoned their community fields, because nobody was willing to invest in the fertility of land that belonged to the group.

There was a general concern about future seed provision, because participants anticipated increased demand for seeds of calliandra and cajanus. The same may be true for technical assistance and extension, as somebody mentioned that there were many farmers for very few technicians.