Intercropping = Doublecropping   updated  21/06/2013

temporary intercropping   permanent intercropping     hedges    cattle    trees  honey bees

Benefits of intercropping

Small farmers are used to intercrop, growing several crops together in order to cover the risk of a crop failure and anticipating on erratic rainfall. In  Tanzania for example the combination of Maize and Beans and Pigeon pea is very common.

If more than one crop is cultivated and harvested with different growing cycles, farmers can use their time more economically.

With a better coverage of the area, weeds are suppressed and nutrients are used more efficiently

Pest and disease incidence is lower with intercropping.

Crops can benefit from each other. For most crops intercropping creates a more favorable micro climate

                                                    

Opinion !!!

1.In many countries, especially in Africa, growing Jatropha is being seen as a typical smallholders and outgrowers activity. Farmers are promoted to simply interplant their crops with Jatropha. This is not!! a good development!! Since the farmers grow food crops on better soils, automatically there will be competition. In simple words: where you plant a bean, you can not plant a Jatropha and vice versa!! On the other hand, planting more than one crop in the same field can have many advantages, when a proper planting model is implemented.

2.Some companies and NGO's are promoting temporary intercropping of Jatropha until the Jatropha stand becomes to dense. They say, it gives the farmer an income during the time that the Jatropha is not yet yielding. This system suggests that a farmer can survive on Jatropha alone, which is not the case. A farmer also needs food, even after the Jatropha starts yielding. Remember, a dense Jatropha stand does not produce optimum yield because of lack of light and plant competition. So temporary intercropping  in a subsistence farming system is fooling the farmer. I have seen many intercrops not growing, because the Jatropha was to big and competing for moisture and sunlight.

 

 

 

 

 

 

 

 

 

 

 

Temporary intercropping.

Monocrop Jatropha plantations roughly take three years to start production. In those three years the Jatropha plants are developing, but so are the weeds. Instead of controlling weeds (which only costs money) the space between the Jatropha can be used to grow cash crops and at the same time improve the soil and keep the weeds down. Beans are the best crops to realise this combination of values. If food production is of a lesser concern and weed control and soil improvement are the main objectives, then a cover crop like Crotolaria juncea does an excellent job and bindes 130 to 220 kg of N per ha. After mowing, the vegetation makes a very good compost or biomass as well. Crotolaria however can not be used as fodder.

Cover Crop production

Soil N

kg/ha

Biomass

kg/ha

Sunnhemp, Crotolarea juncea

130-220

8000-14000

Table from University of Florida.                                  Picture from Forrest&Kim Star

 

 

 

 

 

Permanent intercropping

Lesson 1. There always is a reason that an area is not used by the farmers. It might be to far from the village, the soil might be poor, there might be a dispute regarding the property of the land etc. These problems should not be underestimated and have to be faced first.

To be successful in intercropping Jatropha with other crops (or other crops with Jatropha), farmers should concentrate on every crop with the same intensity. Forget about the story that Jatropha does not require much water and grows on any soil. The production of Jatropha should be embedded as within a normal mixed farming system, with all its needs and attention. Even more, growing Jatropha should go hand in hand with improved agricultural practice for food crops as well, like using better seeds, planting in time and in rows, weeding , using fertilizer or organic manure, etc. etc. This means that in Jatropha promotion programmes farmers should not be compensated with money, but they should be compensated with good agricultural practice training, proper seeds or plants and fertilizers.

Does this mean that Jatropha is (again) competing with food crops? No, with this integrated farming system Jatropha is breaking the way to increase planting area's and increase the production of food crops, resulting in a 1+1=3 result

It means that by planting Jatropha, the food production area  increases as well!!

 

                                

wrong intercropping with maize (Tanzania 2008)                                                  right intercropping with maize (Tanzania 2010)

Jatropha Intercropping Planting Model

The model consists of a double row of Jatropha planted 2x2 (=4 mtr wide) alternated with 6  meter for other crops and/or machinery. This results in 1000 Jatropha plants(4000m2) per ha and still 6000m2 for food crops to grow in between the Jatropha. (See drawing.)

The space in between the double Jatropha rows is a variable. Actually, it is depending on the type of intercrop and/or the equipment which is going to be used.

             

Of course this is just a model. No field will be square like this one. On top of that, if the field is on a slope,  Jatropha should be planted along the contours. Below you see the first trial results, based on this model.

Click drawing to enlarge

 

 

The Max Havelaar fair trade Jatropha feasibility study (By Ab van Peer, Agronomy consultant in this project.)

(Text and comments are the view of the author and not necessarily from Max Havelaar)

 

Under coordination of Max Havelaar Netherlands, Fairtrade Labeling Organizations (FLO) is carrying out a feasibility study into the Fairtrade certification of Jatropha. This project is supported by the Global Sustainable Biomass Fund, a fund commissioned by the Ministry of Foreign Affairs and implemented by NL Agency. Other partners executing the study in the consortium with Max Havelaar and FLO are the development organization Interchurch Organization for Cooperation and Development (ICCO), the energy company Eneco and the Tanzanian farmers union Kagera Co-operative Union Ltd. (KCU) in Bukoba.

Background

The biomass sector could provide economic opportunities for countries in the South, provided sustainability criteria are strictly adhered to. International trade chains do not automatically include smallholders, yet 75% of all poor people in the world live in rural areas and depend on agriculture for their living. When new markets emerge, focused efforts are needed to ensure that smallholders can directly share in the opportunities and returns such markets can bring.

Objectives

The study will assess whether a draft of Fairtrade standards for Jatropha can be implemented

a.      in the management context of small farmers organizations;

b.      avoiding negative (indirect) effects on food security;

c.      contributing to improved farm management, diversification, better local access to energy and additional income on household and community level.


The study will evaluate models for long term economic viability throughout the trade chain. It will investigate the scalability of results, by looking into their applicability in other producing countries and into the possible application of matching Fairtrade principles in the plantation sector. Depending on the outcomes, the study will elaborate proposals for FLO’s licensing, labeling and product composition requirements. The learning of the study will be captured in a guide geared for use in smallholder organizations.

 

The Fairtrade standards aspire to enhance and exceed the existing biomass criteria on two points in particular:

·         The certified producer organization will have a direct, auditable responsibility with regard to food security.

 The pilot aims to test if an increased productivity in food crops can be the outcome of well-managed diversification into Jatropha that deals efficiently and careful with natural resources.

·         The standards will require traders to make a proportion of the energy value of the produced Jatropha available for application and use locally.

Project results

-          Developing Fairtrade criteria and the audit system

-          Setting up a chain and pilots in Tanzania

-          Baseline studies in two other ODA-countries

-          Put together a Jatropha manual for small scale farmers

Current activities

In the first phase of the project (2009-beginning of 2010) a pilot methodology and farmer guidance has been developed. Field orientation and consultation of stakeholders in Tanzania has taken place.  Agronomist training and a growing manual was also realized.

By October 2010 pilots have been started on three different locations (See map)

Each pilot consists of a selection field, a nursery and a demonstration field

      

download manual

Objectives of the demonstration field.

In a completely randomized trial with four repetitions and five treatments the following objectives had to be realized:

 

1.Introduce mixed cropping system for Jatropha and food crops
 
2.Prove that Maize (or other food crops) can be grown together with Jatropha. (Due to rumours and failed plantings there is a perception among the farmers that Jatropha affects other crops negatively)
 
3.Prove that Jatropha seedcake is as good as organic manure as a fertilizer.
 
4.Prove that by introducing good food seed varieties, manure or fertilizer and good agricultural practices, farmers can use 40% of their land for Jatropha without loosing food production. (this requires a 66% yield increase)

    

While the objective was to reach at least 2.46 MT, the seedcake trials performed statistically better. (resp.3.4 and 4.27MT)

In this demonstration trial it was easy to increase maize yield by more than 100% (compared to farmers practice) through implementing sound and simple agricultural practices.

1.preparing the soil well

2.applying manure or Jatropha seedcake

3.planting the right maize variety

4.planting at the right time

5.planting in rows to facilitate weeding

6.weeding in time

The agronomical results are going to be supplemented by economic research in order to define what fair trade standards will have to entail.

In the mean time a farmers guide in Kiswahili has been realized as well.                                                            Download Kiswahili guide here

        

 

 

 

 

 

 

 

 

 

 

 

 

 

The above mentioned trial was repeated in the 2012 rainy season with even better results, as shown on the graph below.

 

 

By using 2 tons per ha Jatropha seedcake at a value of Euro 200 a yield increase of  2.8 tons of maize was realized with a value of Euro 560

Once when his Jatropha plants will yield (1000 plants/ha), he will be able to collect at least 1000 kg of seeds at a sales price of 0.15 which makes another 150 Euro.

If the farmer is a cooperative member, he probably shares in the profit or the savings (in the case of own energy production) the cooperative makes with the Jatropha oil.

 

This is a comparison based on market prices. Costs of labour and handling are not included

 

 

 

 

The effect of Jatropha on poor soils

Initially poor soils will result in poor harvests. You get nothing for nothing. However, in due time a couple of systems are going to work. Jatropha will gradually develop into a large shrub, providing shade and/or shelter to other crops (depending on planting distance). Furthermore the roots of Jatropha grow pretty deep and will touch layers where the normal annual crops or weeds do not reach. The nutrients picked up from these layers are reaching the surface via the Jatropha plants. Through pruning and shedding of the leaves, the nutrients will return to the surface, enriching the upper layer where other crops are intended to grow. As the seeds from Jatropha are pressed, the remaining seed cake should be returned to the surface, because it is rich in N, P and K, equal or even richer than chicken manure.

Nutrient value of Jatropha seedcake from different sources compared with chicken manure.

SAMPLE NR LAB Total N C/N ratio NH3 Phosphate Potassium Mg
232548 Sucofindo (Indonesia) 3.68     1.09 1.59  
501065 BLGG (Netherlands) 4.1 9 0.05 1.88 1.91 0.92
501066 BLGG (Netherlands) 4.23 9 0.05 0.2 2.28 0.106
Internet SRCVO Mali 4.1 13.3 0.1 0.5 1.2 0.4
19201 South Africa 3.46     0.31 1.24  
  Henning 5.7     2.6 0.9 1.26
Chicken manure   3     2.7 1.5  

How can Jatropha benefit from intercropping .

Food in between Jatropha.

Presume  growing beans in between the Jatropha. With a row distance of 6 meter between the Jatropha rows the beans have ample space to grow. The beans or other crops will grow between the Jatropha, protected from strong winds and excessive radiation. After harvest the root systems will deteriorate, providing the soil with nitrogen. On top of that the flowering beans or other crops will attract insects, badly needed for the pollination of the Jatropha. Many crops could be intercropped with Jatropha in a way that the intercrop takes advantage of the Jatropha and vice versa. Farmers should concentrate on the local market. Whenever they can make a good price for melon, they should grow melon in between the Jatropha. The melon crop will make sure that the Jatropha plants get pollinated by insects. Same counts for ground nuts, cow peas, pigeon peas , sweet potatoes, peppers, maize,etc.

RESEARCH NEEDED!!!

Unfortunately I indentified only limited information regarding the influence of Jatropha on the intercrop and vice versa. here

  

Ground nuts in between Jatropha (Thailand, 2007)                                                                   Sesame intercropping in Mali (2009)

Trees in between Jatropha

In principle you should not grow Jatropha in a forest, because the forest creates shade and Jatropha needs sun! However, Jatropha plants could take advantage of existing trees (Acacia) or introduced trees (Prosopis*) because those trees attract insects badly needed for pollination of Jatropha flowers. So why not interplanting Jatropha rows with this kind of pollinator trees. The moment they become to big the wood can be used  for charcoal production or even firewood, creating a sustainable source of firewood and charcoal. Some of the trees are also oil producing (Azadirachta and Pongamia) or nitrogen fixing (Pongamia and Faidherbia albida). Faidherbia albida (Acacia albida) could be a very good intercropping tree in the dryer parts of West Africa, because it drops its leaves during the Jatropha growing season and it gets leaves when the Jatropha goes dormant and drops the leaves.

* There are many varieties of Prosopis and Acacia and some become a weed under certain circumstances. Be sure you verify the characteristics of a plant before you introduce it. More info about Prosopis here

Honey Bees

These trees also have the potential to become important for the production of honey, provided there is water available for the honey bees!!

   

Prosopis juliflora                                                         Acacia sp.                                  Beehives in Tanzania (Same)

Cattle in between Jatropha

It is known that cattle (goats, sheep, cow) do not eat Jatropha leaves. Apparently these animals are not as stupid as we think they are. This means that you can grow Jatropha in grazing area's. They do that in Brazil already. As with food intercropping, ample attention should be given to grow the right type of pasture.

Caution :Jatropha plants have to be well established before grazing starts, otherwise they will be trampled.

Goats eating the weeds between Jatropha seedlings (Lampung, Indonesia, )  Cattle grazing  in Brazil. (Photo D1 and Green Power))

 Plant Jatropha in hedges along boundaries.

I am not promoting stories like "keeping the goats out" or erosion control on a small scale, because there is no scientific proof for it. Did you ever see a goat pushing itself into a fence? As soon as the head passes, the whole goat passes. But at least they do not eat it. I found a report regarding the supposed positive influence of Jatropha on degraded soils, which you can find here.

Boundaries are everywhere. Housing plots, streets, canals, maize fields, soccer fields; they all have boundaries, requiring maintenance. So most of the time these boundaries become a mixture of poles and trees and wire and weeds or in other words, they become a mess and a burden. Why not planting all these boundaries with Jatropha, providing income in stead of costing money.

Hedges can produce a lot of seed. It is estimated from a project in Mali (by Henning) that a hedge could produce 0.8kg per meter/per year. So if an average farmer has a plot of 0.5 ha (100x50 m), he can plant 300 mtr of Jatropha hedge which will bring him 240 kg of seeds. And so will his neighbour, and his neighbour etc. etc. A km of Jatropha hedge can produce 800 kg of seeds.!

Critics are doubting that you can get enough volume out of a smallholder farming system. However, there are plenty of examples that you can! Think about coffee and tea and cotton and strawberries!. Even a lot of oil palm is grown by smallholders. On top of that, the Mali estimation comes from a very dry area and with an increase in rain you will get an increase in yield of Jatropha seeds. How much? We do not know. Agronomists in Jatropha projects are either very secretive or ignorant about collecting  data. This is one of the biggest obstacles for the development of Jatropha. Even the owner of the hedge on the picture below  did not know how much he picked from the hedge. He only knew it was not enough to run a generator. But he could still recollect the moment he planted the hedge. That was 10 years ago. Why? He did not know either. Probably to make soap which was very popular at that time.

 

10 years old Jatropha hedge along a path in Leguruki, Tanzania 2008                  20 year old hedge  in Manako, Mali 2009

Planting Jatropha in plantations outside food production area's.

There is a lot of negative discussion about planting Jatropha in plantations.

 Below are some of the arguments.

One thing is for sure. World wide there is a lot of land available which was used for agriculture 50 years ago. How come?

When adapting a system where Jatropha per definition has to grow with other crops or other agriculture activities like grazing, there is a guaranty that bio fuel production and food production go hand in hand.

This does not automatically mean that food crops and Jatropha should always be mixed in the same field. A good system could be Jatropha/Food crop 50/50 on separate fields. However, in a mixed crop system, the choice of  the right combination will be more efficient, because crops are profiting from each other.

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