‘When it rains’: The role of trees and shrubs in preventing soil erosion

Environment and climate changeSoil healthTrees and agroforestry

Notes to broadcasters

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Erosion is one of the biggest problems that farmers face in regions where farmland slopes and lacks covering vegetation. One rainfall can wash away all that farmers have worked and hoped for. But, for every problem there is a solution. To hold the soil and prevent erosion, farmers can plant fast-growing trees and shrubs between crops.
If your listeners practise farming on gentle or moderately sloping land and have serious problems with heavy rains which erode their soil, they may want to plant trees and shrubs as hedgerows. These hedgerows serve as physical barriers against soil erosion.
This script is a short drama which highlights some solutions to soil erosion. Two ways to use this script are by simply adapting the drama for your local audience, or using it as inspiration to produce your own drama on using trees to prevent soil erosion in your area.

The drama is followed by a question and answer session between an interviewer and an expert on using hedgerow barriers. Please feel free to use this Q & A session as written, along with the drama. Or you can use it as inspiration to invite an expert on hedgerow barriers to your station, and conduct your own interview.

Script

‘When it rains’ part 1

Bring up music and cross fade into effect. Cricket sounds in the distance. Heavy winds blowing. A crack of thunder and then heavy rain. Hold the rain for 3 seconds.
Keke:
(Yawning) Nothing like the morning after a rain. I can not only feel, but smell the fresh air.
Chirping of birds in the far distance
Keke:
Whoa! What a rain, I better go and check my fields. This is going to be my year of bumper harvest … (Shouts) I am off to the farm!
Door opens and closes. Establish atmosphere of countryside environment. Birds chirping. Cows moo in the distance. Cut to someone running through the bush. Then stopping suddenly.
Keke:
No it’s not possible, this cannot be my farm! Tafa, have you seen? All the yams and cassava washed away by just one rain! My God, I am finished!
Tafa:
(Sober, nearly in tears) Keke, have you seen my farm … oh! The rain, how can the gods be so unkind?
Dende:
(Calming voice) Tafa, the gods are not to blame. Most times the fault is ours.
Keke:
Dende, don’t let me take my frustration out on you.
Dende:
(Calmly) Would it solve your problem? Don’t forget it’s not only your farm that was destroyed by the rain.
Tafa:
I am so confused; I don’t know how you can be so calm … Dende, what do we do?
Dende:
(Still calmly) We all suffered the blessings of last night’s rain. The gods want us to learn something from this … let’s go and report this disaster to the village head.
All voices in agreement:
I suppose you are right.
Footsteps in the bush. A stream flows. Birds chirping in the distance. Voices of children fetching water at the village stream.
Tiwa:
Papa Ego, where are you coming from? Why are you all wearing such a face? Did someone die?
Keke:
Tiwa, if someone died we would have been able to face it. But what has befallen us is worse than death.
Tafa:
The rain of yesterday…
Tiwa:
(Cuts in) The rain was a blessing to all the farmers in our village. Didn’t you hear them celebrating and thanking God for opening the heavens?
Quiet murmuring by all the men
Tiwa:
Did I say anything wrong?
Dende:
No, my daughter, your words are full of wisdom. It takes courage to learn from one’s mistake. (Slight pause) Can you do us a favour?
Tiwa:
What can I do, sir?
Dende:
Can you take us to your fields? We would like to see for ourselves. You must be doing something right, and we need to know to survive.
Fade in music and hold under announcer
Announcer:
What do you think is the cause of the problem in Dende’s village? What is the solution to the problem? Tune in for the conclusion of the story, ‘When it rains.’
Hold closing music for 3 seconds and fade

 

‘When it rains’ part 2

Announcer:
To farmers, the rain is a blessing. It brings nourishment to the soil and allows the crops to grow. To farmers, usually a good rainfall means a bumper harvest. But this was not the case for farmers in Bendo village. But wait a minute, don’t they have the same soil as their neighbours in Agbado village? They have been planting crops on this particular soil for generations, so what went wrong? They are about to find out as they follow Tiwa to her village in Agbado.
Bring up music and cross fade into outdoor effect of birds chirping and squirrels trilling in the cool air of the morning. Suddenly, marching feet come to a halt.
Keke:
Tiwa, did it rain here?
Tiwa:
Heavily.
Sound of drumming and celebration filters in from the village
Tafa:
Then how? I don’t…
Dende:
(Interrupting) What Tafa wants to say is…
Tafa:
I believe I can speak for myself. (Slight pause) How come your farms are looking so lush and intact? You grow crops on the same hills as us.
Keke:
(Sad and upset) The gods are not fair. They used an umbrella to protect your land and exposed ours to destruction.
Dende:
(Amused) Do you make sense even to yourself? Our two villages are side by side and God covered their village and exposed ours?
Keke:
(Angry) Dende, you behave as if you are the only sensible person in Bendo village.
Tafa:
Keke, I agree with you.
Dende:
And I agree with the two of you.
Keke and Tafa:
(Shouting) Who do you think you are?
Tiwa:
My fathers – you don’t need to lose your tempers! We are close to my village … let’s join your brothers and we will find the answer to this puzzle.
Sound of footsteps. The sound of drumming becomes louder. As Beke speaks, the drumming fades into the background.
Beke:
Tiwa, my daughter, you brought our brothers to celebrate with us. Dende, Tafa, Keke, my other brothers – you are all welcome to Agbado village.
Bobo:
The rains have come, and to us, when it rains, it blesses the soil and the products of our farms.
Beke:
And that’s why you met us celebrating. But you don’t look happy. Did it not rain in your own village?
Tafa:
(Sorrowfully) The Gods choose to bless you and curse us. It is not fair!
Beke:
Please stop drumming!
Drumming comes to an abrupt end
Beke:
(Continuing) I don’t understand … do you?
Dende:
It rained in our village too, but the result is different. I am still confused. My father before me was a farmer and I inherited his farm, and I have been planting different crops.
Keke:
Dende, you talk too much. The rains came and destroyed our farm land.
Bobo:
(Sympathetically) We at Agbado have gone through that before. But then we learned about farming with trees and that brought us from the brink of disaster to success.
Beke:
You need to see our farms to believe. After all, seeing is believing.
Tafa:
I need to take my own two naked eyes to see this to believe that farmers can grow trees with crops.
Beke:
Please follow me.
Sound of footsteps on the bush path. Birds chirping. Sound of various animals in the distance. They stop.
Dende:
I can’t believe this. You have trees in between your crops!!
Beke:
Yes, you can see that we are growing these rows of shrubs and trees between our crops to protect the land. The roots of the trees help to hold the soil. They also help water to seep into the soil, rather than running off down the hill. We prune the trees so they don’t shade the crops. Then we use the prunings as mulch for our crops. This feeds the soil and makes it fertile.
Bobo:
If not for these trees, our plight would have been the same as yours! Our sorrow and our crops would have washed away.
Keke:
We cut our trees to make firewood.
Beke:
That was your first mistake. You need the trees to control erosion. You can see how our mahogany trees have helped to hold the soil from washing away. These shrubs over here are used as animal feed.
Tafa:
What of the banana?
Bobo:
They perform the same function as the mahogany, but added to that they serve as food for all the village. We even export the bananas to the neighbouring country.
Dende:
Good farming techniques, and not the gods, brought good fortune to Agbado village.
Keke:
We need to learn more from you … we would like to visit your village again, and bring more of our farmers.
Dende:
As soon as you are ready, you are welcome to return. One thing I have learned, my brothers, is that knowledge is power.
Closing music. Hold for three seconds and fade out.
Announcer:
Do you agree with the conclusions made by the farmers in the story? What about your village? Have you tried planting trees to protect and hold the soil in place? Please call in to talk to us at this station to tell us about your experiences. As a special feature today, we have an expert on hedgerow barriers in our studio. Here’s Farmer Ngado to talk more about how you can use trees to help you on the farm.
Ngado:
In the story we have just heard, the farmers in Agbado village planted hedgerow barriers. Hedgerow barriers are one of the simplest and most popular practices used to save soil on sloping lands. Farmers plant fast-growing rows of trees close together along the contours of the slope. The trees form hedgerows, and farmers grow food crops between the hedgerows. When heavy rains hit the earth’s surface, and rainwater runs quickly downhill, these hedgerows stop soil from continuing downhill, and they slow down the flowing water. In the story, the hedgerows helped the farmers keep their soil and their rainwater in their fields where it belongs.

Announcer:
That is all very well, Mr. Ngado. But some farmers might object to planting hedgerow barriers. They may say that taking some of their land out of production to grow hedgerows is not worth it. They will lose money and food because they won’t be planting as many crops.

Ngado:
You are right. Hedgerow barriers are not good for everyone. A farmer has to carefully weigh the benefits and the costs. But if a farmer lives on sloping lands and loses a lot of soil to erosion, hedgerow barriers may be a good idea. Of course, hedgerows have other benefits.

Announcer:
Like what?

Ngado:
Many hedgerow trees are legumes. Legumes feed the soil by dropping their nitrogen-rich leaves, and because their roots are nitrogen-rich. Another benefit is that the hedgerows can be pruned and their wood used for firewood. Or you can cover the soil with prunings to help control weeds. Also, many farmers feed the prunings to their livestock.
Announcer:
How far apart should one hedgerow be from the next hedgerow?
Ngado:
That depends on how steep the hillside is. Usually, hedgerows are planted on contour lines which are two metres or less apart.
Announcer:
You have used these words “contour lines” twice now. But what are contour lines?
Ngado:
Contour lines are imaginary lines that run across a slope at the same height and do not run uphill or downhill. So, when I say that hedgerows are planted on contour lines not more than two metres apart, I mean that there should be a vertical drop in height of less than two metres between one hedgerow and the next. This might mean that the hedgerows are six metres apart. But they could be much farther apart if the slope is more gentle. It all depends on how steep the slope is.
Announcer:
How do farmers plant hedgerows?
Ngado:
Usually, farmers either raise seedlings in their nurseries or plant seeds directly into the soil at the beginning of the rainy season. The plants should be close to one another so that they form a thick hedge. Once they reach shoulder height, the trees are cut back to just 20–30 centimetres tall. They will grow back quickly. You can keep growing and cutting back the trees back like this for many years.
Announcer:
So, farmers plant the seeds or seedlings close together. And then they cut them back when they reach shoulder height. Is that right?
Ngado:
Yes, exactly.
Announcer:
This method sounds like it doesn’t cost very much. But doesn’t it require a lot of labour to prune the trees?
Ngado:
You’re right – it does require a lot of labour. But if you don’t cut them back regularly, they will grow tall and thick and compete with the crops. So a farmer has to decide for himself or herself whether this extra labour is worth it.
Announcer:
Are there any areas where hedgerow barriers should not be used?
Ngado:
We don’t encourage hedgerow barriers – or any other crop growing – on very steep slopes, more than a 20% grade. It’s best to plant these areas with trees.
Announcer:
What about dry areas?
Ngado:
Hedgerows are difficult to establish in dry areas, but are extremely valuable. Dry areas are very prone to erosion and hence desperately need the hedgerows. The mulch from the hedgerows improves the capacity of the soil to hold water and protects the soil from direct sunlight. This reduces evaporation. Fodder from hedgerows is vital in dry areas.
Announcer:
What kinds of trees should you grow in hedgerows?
Ngado:
That depends on where you live. Talk to your extension adviser for advice on that question. But it’s often a good idea to grow leguminous species. Legumes feed the soil and make it fertile. And they have deep roots that do not compete very much for water with crops.
Announcer:
Thank you, Mr. Ngado. (Pause) That’s our show for today. If you have any questions about growing hedgerow barriers, please phone, text or mail us your questions at the station. We will try to answer them ourselves – or find someone who can! Thanks for listening.

Acknowledgements

  • Adapted from Farm Radio International Package 74, script 3, written by the African Radio Drama Association (ARDA), Lagos, Nigeria, a Farm Radio International broadcasting partner.
  • Reviewed by: Peter Gaichie Kimani, consultant to World Agroforestry Centre (ICRAF), Nairobi, Kenya.

Information sources

  • Ed Verheij, 2003. Agroforestry. Agrodok 16. Agromisa Foundation, Waginingen. http://www.journeytoforever.org/farm_library/AD16.pdf, p. 33-37.
  • Trees outside forests: agro-, community, and urban forestry. New forests, Vol 17, # 1-3, January 1999, Pages 145-174./