No. 93 What is Rainforest Saver doing?
By Tiiu-Imbi Miller | Ultimas Noticias No. 93 May 2019

Apologies for the recent lack of newsletters, caused by a combination of lots happening (yes, the more there is to tell you the harder it is to do the telling) and illness in the family. 


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Our Aim

is to replace unsustainable slash and burn farming in tropical rainforest areas with sustainable Inga alley cropping. This will give the farmers a better living on the same plot of land because the Inga system keeps it fertile long term so that they no longer need to clear more forest. A win-win all round. Cash crops are valuable and many different ones can be grown in Inga alleys, but we put the emphasis on the farmers growing food for their own and local consumption, rather than just export crops, as favoured by many development NGOs. We hope that in time the farmers will achieve food sovereignty – independence in food production, invaluable in our uncertain world with an expanding population.


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Collecting the harvest from an Inga alley plot. Photo Gaston Bityo


What is Inga alley cropping?

            Inga trees are legumes (like peas and beans). Legumes fertilise the soil. Plants need nitrogen compounds to grow, but cannot use the nitrogen in the air directly. Legumes make it available with the aid of special bacteria in their roots. They also recycle minerals, like phosphorus, with the aid of special root fungi (mycorrhizae). In alley cropping, Inga trees are planted in rows, with spaces, the alleys, between the rows. The trees grow, close their canopies across the alleys and lack of light kills the weeds, much to the farmer’s delight.  Then the trees are pruned. The big branches provide good quality firewood, while the leaves are left to rot down into a rich mulch in the alleys. The crops are planted into this mulch. After harvest the trees regrow, and the cycle is repeated year after year.


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From the left: a mature Inga alley at CURLA (part of the National University of Honduras), a pruned Inga alley ready for sowing the crop, and young maize in a weed free Inga alley (first photo Tiiu Miller, the other two Gaston Bityo)


How does Inga alley cropping differ from other farming techniques in the humid tropics?

            It is an organic system, without the need for artificial fertilisers, herbicides or pesticides. Hence it is safe and cheap. Once the farmer has got some trees to start off he can propagate them and increase his plot size as much as he likes.

            It is also a very simple system so that it can be spread easily, and should spread from farmer to farmer once it is well established in a region.


Description: Macintosh HD:Users:tiiuimbimiller:Inga Project:Website_Newsletter:February- April/May 2019:WebNewletter93:3-Inga-seeds-under-the-shelterWeb.jpg

A small nursery, such as one that any farmer could set up cheaply and easily. Photo Gaston Bityo.


What sort of yields does it give?

            Dr. Valle in Honduras has been working with Inga for many years and reported yields of crops grown in the Inga alleys at CURLA (part of the Autonomous University of Honduras) as up to 2 ton/ha of corn (maize) and 1.4 ton/ha of beans. That would mean that a 2ha plot would provide for the needs of a family of 8 and leave a surplus to sell.  Our own little rough on-farm experiments in Cameroon suggest that even higher yields can be got.

            This compares favourably with what is currently obtained in a lot of small scale tropical farming, but is a lot less than what is obtained by industrial farming. The latter however depends on huge, expensive inputs (fertilisers, pesticides, tractors etc), and damages the soil in the long term.


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Tall maize growing well in an almost weed free Inga alley. Photo Gaston Bityo.


Where do we work?

            Cameroon. Our local partner is Gaston Bityo Delor, founder and head of Volunteers Serving Development, Cameroon. He contacted us in 2009 and we have been working together ever since. He trained 4 other community leaders as Inga promoters with a grant from the Guernsey Overseas Aid Commission in 2016 and these have been taking the technology to farmers in their areas.  There is considerable demand for it in Cameroon. Besides working directly with farmers several schools have been included.

            The local Inga promoters are Atanga Wilson, Linus Arong and Tabouguie Alphonse. All these are in the Anglophone region. Gaston Bityo himself is from the Francophone and has worked with individual farmers, several villages and the Baka (pygmies) in the South and Eastern parts of Cameroon.



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Ecuador.  We work through a local agricultural college.  Staff from the college supervise the work. We are employing a full time assistant for them.

            Honduras.  The main project there is with schools, overseen by Dr. Guillermo Valle. This project stalled for several years because of problems of finding a good assistant for Dr. Valle. We now welcome Ronald Ramos in that role, and the work has resumed. Schools not only educate the future generation but parents are invited in to see Inga alley cropping and helped to try it themselves if they desire.


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Dr, Guillermo Valle teaching high school students in an Inga alley at FunaVid in Honduras. Photo Tiiu Miller.


            Besides work with the schools Dr. Valle is doing relevant research, in particular to test other trees to see what else could be used in a similar way to the Inga. The Inga is a particularly good tree for the purpose, and was selected from many others that were tried, but it is not best practice to depend on one species.

            The second small project in Honduras is by Marco, who is introducing a small number of farmers to the Inga technology in the steep slopes of the Cangrejal valley.  When planted correctly along the contours Inga resists erosion and so is doubly valuable in this location.



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Rows of young Inga on a steep slope in Honduras. Photo by Marco.


            Kenya. One of our Cameroon colleagues has moved to Kenya and is starting an Inga project there. He has been welcomed by the locals.

            Sierra Leone. This is Antony Evan’s (Rory’s Well, project. He invited Gaston Bityo to take the Inga to Sierra Leone and train his people there in how to do it.


How do we work and with whom?

            All the field work is done by local colleagues, many of whom (all of the ones in Cameroon) contacted us, rather than us seeking out collaborators or employees.  We hope that this will ensure that the technology will become well integrated into the local society.


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Gaston Bityo, overall head of the Cameroon Inga Project


Inga alley cropping is not a quick fix. Even in the tropics trees need a couple of years to grow. We provide resources (money, advice, oversight) to establish nurseries and give farmers small quantities of Inga seedlings to establish starter plots to convince them of the value of this system. We cannot expect the system to spread much until people have seen good results for themselves, and until there are several productive plots to show in the different regions. So although our ultimate aim is independence for the farmers and the work to be taken over by local leaders, we will need to support these projects for several years before that can happen.


Description: Macintosh HD:Users:tiiuimbimiller:Inga Project:Website_Newsletter:February- April/May 2019:WebNewletter93:comparisonWeb.jpgFertile Inga alley on the left and land devastated by repeated slash and burn farming



With best wishes, and thank you for subscribing to our newsletter,




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