SEATTLE — The word ‘dirt’ is often used with a negative connotation in the United States. But for a gardener or farmer, the first mental image of dirt may be all the different soil types they have encountered, from rich, peaty soils that smell almost sour to dry, dusty, alluvial soils that smell like iron. They may also remember all the creatures they encountered while working with that soil: a bird’s nest hidden among brush, purple mushrooms, earthworms, brightly colored plant roots and more that create a hidden, diverse ecosystem.
Soil is humanity’s life blood. Its chemical and biological makeup determines what plants farmers grow, how well and how much. It is those decisions that ultimately determine what food we find on our dinner tables.
But imagine a community where the farmers who grew food were dependent on soils so exhausted from erosion and nutrient depletion they had to pick up every few years and begin anew. That has been the experience of thousands of farmers in Honduran hillside farming communities for decades.
The Lempira region of Honduras is home to many such communities. It is located in the southwestern corner of the nation bordering El Salvador. Thousands of residents farm small plots of land among hilly terrain with slopes that are at 30 percent angles or greater.
Soils along these slopes are what scientists call Entisols, meaning they are loamy, gravelly in texture and acidic. They have little organic matter and phosphorus, both important for plant growth and health. They are also very shallow.
The Honduran dry season that runs from November to April can bring harsh droughts. In contrast, the wet season running the following six months can bring storms and hurricanes. These extremes in weather can leave farmers with inadequate water for their crops part of the year, or cause a damaging and dangerous deluge.
The climate is not the only cause of poor soil. Farmers in the Lempira region traditionally cleared their land by slash-and-burn. This method allows farmers to clear the land quickly by cutting down all vegetation and setting it on fire. However, it reduces soil health over time.
Vegetation cover is necessary to protect soils from erosion and water loss while recycling nutrients, and also provides the organic material to support a diverse soil ecosystem. Plant roots help to hold the soil in place while vegetation cover reduces evaporation. In contrast, the slash-and-burn method of clearing leaves a plot of land empty and exposed to the elements.
Under such conditions, farmers found they could not support a decent harvest on any particular plot for more than a few years. The rapid clearing of land all across the landscape was causing massive environmental degradation while deepening local communities in a state of financial and food insecurity and impoverishment.
In addition, such degradation increases the chance of landslides and floods putting residents at great risk of environmental disasters. In October 1998, Hurricane Mitch ravaged Honduras, destroying lives, crops and infrastructure including roads, bridges, buildings and upwards of 200,000 homes, leaving thousands homeless. More than 5,600 Hondurans lost their lives.
With such harmful short and long-term impacts, made more apparent by a disastrous drought in 1987, the Honduran government partnered with the Food and Agriculture Organization (FAO) and local farmers in Lempira to develop a system that would create greater food security and environmental sustainability while reducing poverty.
It was called the Quesungual Slash-and-mulch Agroforestry System (QSMAS), or the Quesungual system after the very old, small town where it was first developed and implemented in 1992.
The Quesungual system integrates forestry and agricultural methods to create a three-tiered landscape that diversifies crop production while restoring soil health and water capacity.
The first step is to choose a plot of well-grown second-growth forest and the trees that will be kept and maintained. Usually, trees that can provide timber and fruit are chosen. The second step is planting and fertilizing the crops. Often farmers will begin by planting what are called pioneer plants such as sorghum or beans whose seedlings are strong enough to push through a layer of mulch. Additional crops like maize and vegetables are planted later. If herbicides are used, they are usually sprayed before planting. Fertilizers are carefully measured out and applied for greater efficiency.
After planting, the trees are pruned to allow enough sun exposure, while the branches and foliage pruned from the trees and crops or cleared away before planting are laid out carefully to completely cover and protect the soil. The soil is never tilled so as to maintain the structure and further reduce erosion and water loss.
Numerous studies have revealed great successes since the Quesungual system was first implemented. One study found that soil loss was five times greater and water loss by run-off 25 to 60 percent greater for slash-and-burn plots. Another study found that in Quesungual systems maize production increased by 54 percent while bean production increased 66 percent. It was also found that the greater water retention allowed crops to be grown for an additional 20 days without rainfall, often the only source of water for farmers.
These advances have allowed farmers to increase annual production on the same land for much longer periods and with less labor. They have greater incomes, more food, greater flexibility to diversify their produce and can increase their community engagement. With such success, the Quesungual system has been introduced to other regions of Honduras, Nicaragua and Colombia.
– Diana Nightingale
Photo: Flickr