Trees for food security in Eastern Africa

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Clemence shows bank account and family insurance certificates paid for with proceeds of tree tomato sales. Photo by A. Mamo/ICRAF

By Akefetey Mamo, originally published at ICRAF’s Agroforestry World

Eastern Africa is home to four out of the nine hunger hotspots in Africa. Across much of the region declining soil fertility coupled with lack of resources to afford inherently risky inputs such as fertilizers, constrains crop production.

For millions of smallholder farmers these problems are exacerbated by more frequent and extreme weather events including droughts and floods associated with climate change. It has been established that trees on farms can contribute to improving food security – directly through food provision (fruits, nuts, and leaves) and indirectly both, from the sale of tree products generating income that is then used to purchase food, and through system intensification, where trees improve soil fertility and the regulation of water flow increasing crop yields.

Often, intermediate tree products such as fodder and fuelwood produced on farm save labour otherwise used to collect them, that can then be used for other intensification options and trees are associated with higher abundances and activity of beneficial soil organisms that promote long term soil health. Trees may also buffer temperatures, useful in adapting to climate change.

“Working across field, farm and landscape scales, it is known that trees can play a key role in making efficient use of water and nutrients while maintaining soil carbon.” says Fergus Sinclair, Systems Science Leader at the World Agroforestry Center (ICRAF) headquartered in Nairobi, Kenya, “this can be instrumental in developing a climate smart agriculture through the intensification and diversification of farm production.

Further they can also have knock on effects within farm systems. For example in Ethiopia, if instead of using dung for fuel, farmers get firewood from farm trees, they can return the dung to crop fields and improve yields, while in Rwanda stakes from pollarded trees can be used to support climbing beans that increases bean yields.”

While these processes are understood in principle, it remains a key research challenge to match tree species and management practices to the range of farm circumstances encountered across Eastern Africa and predict their impact on food security.

Understanding structures and tailoring options to contexts

The potential of the right trees as eco-efficient options for farmers is demonstrated through the work of projects such as the ICRAF led multi-partner effort known as the Trees for Food Security Project (T4FS). T4FS targeted two key agro-ecologies: highland humid and lowland semiarid areas in Ethiopia and Rwanda, eventually scaling out lessons learned to similar agro-ecologies in Burundi and Uganda. The aim was to demonstrate evidence and select the most appropriate options for thirty thousand farmers across representative contexts in the rural regions where an estimated 10 million people are facing acute food insecurity.

“Analyzing and understanding the selected farming systems before designing intervention mechanisms was key to address the barriers to farmers enhancing tree cover on their farms” says Catherine Muthuri, a Research Scientist at ICRAF leading the project, “it was an important activity that helped us to target appropriate interventions by supporting matching of species and management options to the sites and circumstances of the farmers.”

The food security and agroforestry conditions of the farmers and their landscapes was characterized and mapped through seven large scale baseline studies.  Ranging from the biophysical to the socio-economic, including studies on extension systems, seeds and seedlings systems, rapid market appraisals and local knowledge studies, the baselines further provided an understanding of farmers’ decision-making processes and shed light on pertinent issues such as policies, institutions, governance and germplasm management to guide T4FS implementation mechanisms.

According to Miyuki Iyama, an ICRAF socio-economist who with her team, published a seminal study on farmers’ decision-making process in Ethiopia’s Oromia State, “this ‘Options by Context’ approach is essential to meet tree-growing targets, be they local, regional or global. Such an approach will be key to meeting country-led efforts such as AFR100, which seeks to restore100 million ha of land in Africa by 2030.” (Read more of the story here).

A key finding was that farmers were using a far more diverse range of tree species in particular farm and landscape niches than had previously been appreciated. A key baseline in selecting trees is knowledge of the natural vegetation and while there were already maps for some countries a new map was developed for Burundi and integrated within ICRAF’s Vegetation map for Eastern Africa, and tree species selection tools were developed for Rwanda and Ethiopia. According to Leigh Winowiecki, a Soil Systems scientist at ICRAF, “the tools provide spatially explicit analysis for improved targeting of interventions, including identification of erosion hotspot mapping across the action sites”.

Strengthening productive farming systems

The efforts of the T4FS partnership between primary national research partners such as the National Forestry Resources Research Institute (NAFFORI)Rwanda Agriculture BoardEthiopian Institute of Agricultural Research (EIAR)Institut des Sciences Agronomiques du Burundi ; development partners such as World Vision  as well as CGIAR organisations such as CIMMYT and the International Livestock Research Institute has been crucial to the success of its objective.

Preliminary results show that quick win benefits for household nutrition and incomes for a number of families have been generated from the sale of products from fast growing grafted fruit and fodder trees, better access to markets through knowledge and negotiation skills, and higher crop yields from using stakes for climbing beans and tree litter as mulch.

This is exemplified in the transformational stories of women such as Clemence Mukarugwira, a farmer trained in the grafting and management of tamarillo (tree tomato) at the Karago Rural Resource centre in Rwanda, as well as women of the Elgon Women’s Trust in Uganda (ELG) who are now employers and job creators in their community. (Read their stories here).

Clemence was able to sell a 100 kg of tree tomato in the first year of establishment realising an income of 80,000 RWF (125 USD) and doubled this in the second year, enabling her for the first time to open a bank account and purchase health insurance for her family. She has already trained another 20 women in how to grow tree tomato.

The domino effect of transformation are also exemplified through the stories of people like Samuel, a casual labourer who used to work for ELG in Uganda. Samuel left ELG to open his own nursery just across the street from his employers. By combining his wit and knowledge acquired from the project, Samuel says he now makes an additional income of between UGX 500,000 (USD 152) and UGX 1 million (USD 303) per year from the nursery which he says allows him to send four of his children to school. (Read his story here)

Edushe Guye, a farmer in Gerbi village in Ethiopia, explains his innovations to Abayneh Derero, EIAR project lead in Ethiopia. Photo by Albert Mwangi/ICRAF

In Rwanda, the Gishwati Umugunda: a national farmer’s cooperative system, have been instrumental in saving the community’s sloping lands from erosion through the incorporation of Alnus acuminata trees. According to Athanase Mukularinda, project lead at ICRAF Rwanda,“the Alnus trees are improving the productivity of farm lands and have additionally had a positive effect on the rehabilitation of Lake Karago – one of the most important lakes in the region at thee intersection of the Nile and Congo watersheds which was badly affected bysoil sedimentation”.

T4FS led to approximately 250,000 trees being generated in the rural resource centre and planted on over 50 ha of land in key places within the ‘model forest’ being established through a Government initiative with a number of partners. The fast growing Alnus acuminata trees are also replacing napier grass as more effective and longer lasting stakes for climbing beans, enabling a tripling of the bean yields. This simple solution is a very important outcome for the people of Rwanda who eat beans more than anything else says Gislain Tenge Asene of the Rwanda Agricultural Board (RAB). (Read the story With climbing beans, farmers are climbing out of poverty, nutritional insecurity)

Skills, knowledge and capacity building

T4FS spawned innovations in information and knowledge-delivery mechanisms for agroforestry uptake such as Rural Resource Centres (community based and entrepreneurial initiatives combining nursery production with provision of other inputs and knowledge about how to use them). These have not only been instrumental in supporting access to knowledge and much needed high quality germplasm, especially to women and jobs to unemployed young people, but also as a model that is now being replicated.

Six resource centers were established during the project in Rwanda, Ethiopia, Uganda and Burundi and they contrinue to provide extensive training on nursery and grafting technologies as well as seedlings to members and extension agents. (Read about Rural Resource Centers here). Data shows that close to four thousand smallholder farmers are trying out some form of agroforestry intervention, which is contributing to their food security. Through the project, about 2 million tree seedlings have been provided to farmers across the project sites and their performance is being monitored through innovative data collection protocols developed with farmers.

According to Dr. Mark Cyubahiro Bagabe, Director General of the Rwanda Agricultural Board (RAB), “partnership and knowledge acquisition methods in the project have been and will continue to be instrumental in realizing the policy of the Rwandan Government to cover 2 million ha of land with agroforestry. Having seen the successes achieved, RAB will invest in establishing a further seven rural resource centres across the country”.

Knowledge and capacity building has also been a key outcome for the project says Catherine Muthuri, where the active involvement and deliberate policy to train national researchers through formal and informal mechanisms will ensure continuity long after the project ends.

Understanding tree crop interactions in different species and contexts

Integrated tree and cropping system innovations in long term and participatory trials form part of the project’s major initiatives. Yields depend greatly on the context of where and how the crop is grown, including the Agro Ecological Zone (AEZ), site characteristics, the tree and the crop species being intercropped, and the management practices being used.

Predictions of impacts of tree species and management on crop productivity, water resources and nutrients at field, farm and landscape scales are allowing quantification of impacts across a range of contexts. Currently four long-term tree diversity trials are running, alongside more than 20 controlled on farm and on station trials of various agroforestry options, involving over 5,000 farmers. These show both complementarity and competition between trees and crops depending on sites, species and management.

In Ethiopia, for example, wheat yields increased by 28% – 43% under the canopy of unpruned Faidherbia albida trees – a nitrogen-fixing, acacia-like species found throughout African savannas. In contrast, in Rwanda competitive effects of Grevillea robusta on maize were reduced by pruning to control tree water uptake so that maize grown under pruned Grevillea robusta was 15% to 29% higher than a control with no trees but under unpruned Grevillea robusta maize yields were 29% – 57% lower than the control.

Farmer Richard Naumunya in Uganda explains about the sap flow instruments he is hosting as part of the on-farm trials. Photo by May Muthuri/ICRAF

Trees could be critical for adapting to climate change according to Frédéric Baudron and his team at CIMMYT, a CGIAR partner on the T4FS project. Their study showed that “maximum temperatures under the canopy of Faidherbia albida were consistantly 4 to 5°C lower than temperatures outside the canopy – this led to a longer grain filling period and higher yields.

By 2050, the maximum daily temperature in wheat-growing areas of Ethiopia is predicted to rise by 3°C. This could significantly reduce yields of wheat, a crop that accounts for 18 percent of Ethiopia’s cereal area and nearly a fifth of its cereal production. The crop is key to the food security and incomes of smallholder farmers who grow it and using trees to buffer high temperatures could be an important adaptation strategy” they add. (Read highlights of CIMMYTs achievements in T4FS here).

Richard Namunyu, an innovative lead farmer who hosts some of the long term trials in Uganda says it had been instrumental for him to be involved in the trials.  “Farmers usually plant trees without prior knowledge of how they behave towards other crops and the environment as a whole” he says and adds that the experience with hosting research has led to much knowledge he hadn’t known before which others farmers are now keen to tap into.

Modelling tree-crop interactions

Substantive progress on agroforestry modeling has also been made with T4FS partner CSIRO, the Commonwealth Scientific and Industrial Research Organisation in Australia. According to Philip Smethurst of CSIRO “Until now global models of crop production have ignored trees, despite significant tree cover on much of the world’s agricultural land. This is now changing thanks to a new tree-crop modeling initiative”.

CSIRO has commenced coding of what is called the APSIM agroforestry module using a new APSIM version (working title APSIMX). The model can now simulate crop and pasture production under trees by taking several important positive and negative tree-crop interactions into account (Read more about the model here).

According to Tony Bartlett, the Forestry Research Program Manager at the Australian Centre for International Agricultural Research (ACIAR) under whose portfolio the project lies, “the Trees for Food Security project was very successful. It generated some new high-quality scientific information on tree-crop interactions, established a tree-crop modelling capability within the CSIRO APSIM model, which is of global utility, and enhanced the knowledge and capacity of over 30,000 people in East Africa. In doing so it provided a very strong foundation for follow on research and development activities under the second phase of the ACIAR funded project.”

“Trees for Food Security has been a very important project for us,” adds Fergus Sinclair, “it is because of our partners that we have managed to reach thirty thousand farmers in one way or another, some with a few improved high value trees others with transformational change through adopting income generating agroforestry practices, but through research we have also levered improvements in the understanding of a number of issues that affect food security on farms.

“These encompass improved understanding of tree-crop-livestock interactions at field and farm scales and their impacts on water resources and soil health. We’ve revealed that extension staff need a diverse set of species and management options that can be tailored to sites and farmer circumstances; we’ve shown what seed and seedling systems and associated extension approaches work best in different contexts as well as the system interaction effects of enhancing tree cover for food security on rural livelihoods.

“This will have continued long term effects on transforming the lives, livelihoods and landscapes of Eastern Africa’s rural people long after the completion of the project. We are delighted that ACIAR have agreed to fund a second phase with major national co-investments including an invitation from the Ministry of Agriculture in Ethiopia to assist in developing a national platform for scaling agroforesty and a commitment from RAB in Rwanda to establish seven additional rural resource centres.”

T4FS has produced an extensive list of publications, engagement processes and dissemination activities that were critical to effecting the changes described in this outcome story and continues to produce more.

The links to the publications and outputs can be found here:

Project locations: BurundiEthiopiaRwandaUganda

Project time frame: June 2012 to Nov 2016

Funding: Australian Centre for International Agriculture Research (ACIAR) and the CGIAR Research Program on Forests, Trees and Agroforestry (FTA)

Partners: Ethiopian Institute of Agricultural Research (EIAR), Rwanda Agricultural Board (RAB), National Forestry Resources Research Institute (NAFFORI), Institut des Sciences Agronomiques du Burundi (ISABU), Commonwealth Scientific and Industrial Research Organisation (CSIRO), International Maize and Wheat Improvement Center(CIMMYT), lnternational Livestock Research Institute (ILRI), World Vision led by the World Agroforestry Centre and funded by the ACIAR and FTA.

We would like to thank all donors who supported this research through their contributions to the CGIAR Fund.

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