News / Africa

Feed the Soil, Feed the Crops

Using Evergreen Agriculture, Rhoda Mang’yana grows maize near Faidherbia trees to improve crop yields and soil fertility on her farm. (Credit: Jim Richardson)
Using Evergreen Agriculture, Rhoda Mang’yana grows maize near Faidherbia trees to improve crop yields and soil fertility on her farm. (Credit: Jim Richardson)
Joe DeCapua
If African farmers are going to feed the continent, they may first want to feed the soil. Studies show farmland is often depleted of vital nutrients. But researchers say a combination of organic farming methods may help.



Since the global food crisis several years ago, greater investment is being made in smallholder farms. Most of the farms in sub-Saharan Africa are smallholder, consisting of about one or two hectares. One of the goals is to boost yields without necessarily clearing more land to grow additional crops.

Washington State University researchers say that can happen with greater use of an agricultural system called perenniation. It mixes food crops with trees and perennial plants. Soil scientist John Reganold co-wrote an article about it in the journal Nature.

“This system that we call perenniation is one of those systems where you actually plant perennials and it increases both food security and it builds the soil at the same time,” he said.

There’s an old saying that you are what you eat. Plants need nourishment, too, and they get it from the soil.

He said, “One of the major problems is that the soils are fairly poor in most of the regions. And so how do you grow food on poor soils? There have to be food production systems that can build the soil and improve the yield.”

Reganold said that poor soil may have resulted from years of weathering that leaches many of the nutrients. But in some cases farmers may have done more harm than good.

“They have been actually using farming practices where they’re not putting in organic matter. They’re not putting in fertilizers. They can’t afford those things. And it just runs the soil down more. So they’re actually mining the soil. So they’re worsening the situation,” he said.

He said that the major nutrients that farmland needs are nitrogen, phosphorous and potassium.

“The big one,” he said, “is nitrogen. That’s the nutrient that the plant demands the most and that’s the fertilizer that’s mostly needed.”

He estimated that up to two billion dollars worth of nitrogen, phosphorous and potassium is lost from African soil each year.

That’s where perenniation comes in. It adds nutrients back into the soil.

“We came up with the term perenniation, but the systems have been around for a while. We use the term perenniation. It defines three systems that are already used in Africa. The oldest of the three is called evergreen agriculture and it’s where farmers actually plant trees with their crops. And they’ve been doing this to the best of my knowledge for 60 years, but it’s starting to gain ground,” he said.

It’s gaining widespread use in countries such as Niger, Burkina Faso, Malawi and Zambia, among others. The trees are planted among maize, millet or sorghum. They not only add nitrogen to the soil through their roots, but also through their leaves when they fall off and decay. At other times of the year the trees can shade plants from the harsh sun. Reganold said colonial English and French farmers believed crops should be separated from trees, not mixed together.

Besides planting trees, the perenniation also calls for the use of the doubled-up and the push-pull systems. The doubled-up system has farmers mixing pigeon pea plants among soybean and maize crops. Pigeon pea, a large shrub, adds nutrients to the soil, but can later be used for fuel and fodder. Some parts are edible.

The push-pull system also uses perennials, such as napier grass, which is grown around the maize, and desmodium, which is planted among the stalks. Reganold says desmodium 
is a natural pest management system. It pushes away the stem bore moth from the crops, while the napier grass pulls or lures the moth to the perimeter of the crops. Thus push / pull.

Reganold gave an example of one woman who had great success with perenniation.

“She’s a grandmother in her 50s. Her name is Rhoda Mang’yana and she started using this system about 20 years ago. She used actually two of the systems – the doubled-up legume and she also started using these evergreen agriculture trees. And her yields initially were about a ton of maize per hectare. Now with a good year she gets four tons per hectare. Four times what she was getting,” he said.

Reganold and his colleagues said millions of dollars should be invested in perenniation each year. He hopes development NGOs will take up the cause. Reganold co-wrote the Nature article with Jerry Glover of USAID and Cindy Cox of the International Food Policy Research Institute.

You May Like

Video Iran Nuclear Deal Becomes US Campaign Issue

Voters in three crucial battleground states - Florida, Ohio and Pennsylvania - overwhelmingly oppose nuclear deal with Iran More

Al-Qaida's Syria Affiliate Reemerges

Jabhat al-Nusra has rebounded, increasingly casting itself as a critical player in battle for Syria’s future More

Lessons Learned From Katrina, 10 Years Later

FEMA chief Craig Fugate says key changes include better preparation, improved coordination among state, federal assistance agencies More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Colombians Flee Venezuela as Border Crisis Escalatesi
X
August 27, 2015 2:08 AM
Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Colombians Flee Venezuela as Border Crisis Escalates

Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Is China's Economic Data Accurate?

Some investors say China's wild stock market gyrations have been made worse by worries about the reliability of that nation's economic data. And some critics say the reports can mislead investors by painting an unrealistically-strong picture of the economy. A key China scholar says Beijing is not fudging ((manipulating)) the numbers, but that the economy is evolving quickly from smoke-stack industries to services, and the ways of tracking new economic activity are falling behind the change. V
Video

Video Next to Iran, Climate at Forefront of Obama Agenda

President Barack Obama this week announced new initiatives aimed at making it easier for Americans to access renewable energy sources such as solar and wind. Obama is not slowing down when it comes to pushing through climate change measures, an issue he says is the greatest threat to the country’s national security. VOA correspondent Aru Pande has more from the White House.
Video

Video Shipping Containers Provide Experimental Housing

Housing prices around the San Francisco Bay area are out of reach for many people, so some young entrepreneurs, artists and tech industry workers are creating their own houses using converted shipping containers. But as VOA's Mike O’Sullivan reports from Oakland, the effort requires ingenuity and dealing with restrictive local laws.
Video

Video Arctic Draws International Competition for Oil

A new geopolitical “Great Game” is underway in earth’s northernmost region, the Arctic, where Russia has claimed a large area for resource development and President Barack Obama recently approved Shell Oil Company’s test-drilling project in an area under U.S. control. Greg Flakus reports.
Video

Video Philippine Maritime Police: Chinese Fishermen a Threat to Country’s Security

China and the Philippines both claim maritime rights in the South China Sea.  That includes the right to fish in those waters. Jason Strother reports on how the Philippines is catching Chinese nationals it says are illegal poachers. He has the story from Palawan province.
Video

Video Technique May Eliminate Drill-and-Fill Dental Care

Many people dread visiting dentists because they're afraid of drills. Now, however, a technology developed by a British firm promises to eliminate the need for mechanical cleaning of dental cavities by speeding a natural process of tooth repair. VOA’s George Putic reports.
Video

Video China's Spratly Island Building Said to Light Up the Night 'Like A City'

Southeast Asian countries claim China has illegally seized territory in the Spratly islands. It is especially a concern for a Philippine mayor who says Beijing is occupying parts of his municipality. Jason Strother reports from the capital of Palawan province, Puerto Princesa.
Video

Video Ages-old Ice Reveals Secrets of Climate Change

Ice caps don't just exist at the world's poles. There are also tropical ice caps, and the largest sits atop the Peruvian Andes - but it is melting, quickly, and may be gone within the next 20 years. George Putic reports scientists are now rushing to take samples to get at the valuable information about climate change locked in the ice.
Video

Video French Experiment in Integrating Roma Under Threat

Plans to destroy France’s oldest slum have sparked an outcry on the part of its Roma residents. As Lisa Bryant reports from the Paris suburb of La Courneuve, rights groups argue the community is a fledgling experiment on integrating Roma who are often outcasts in many parts of Europe.
Video

Video Kenyans Turn to Agriculture for Business

Each year Kenyan universities continue to churn out graduates for the job market despite the already existing high rate of unemployment among youth in the country. Some of these young men and women have realized that agriculture can be as rewarding as any other business or job, and they are resorting to agribusiness in large numbers as a way of tackling unemployment. Rael Ombuor reports for VOA.
Video

Video First Women Graduate Elite Army Ranger School

Two women are making history for the U.S. Army by proving they are among the toughest of the tough. VOA's Carla Babb reports from Fort Benning, Georgia as 94 men and those two women rise as graduates of the difficult Ranger school.

VOA Blogs