How to achieve both ecological and
economical advantages:
The creation
of live nopal fences

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Region South America
Capital Quito
Surface area 283,561 km2
Population 13,419,000 inhab.
Population density 47 inhab./km2
Infant mortality rate (per thousand births) 25
Fertility rate (births per woman) 2.8
Population growth rate (per annum) 1.4 %
Life expectancy (female-male) 77 – 71 years
Forest area 38 %


The province of Loja is located at the border with Peru in the southern part of Ecuador. Geographically, the area is characterized by an extremely irregular mountain range where few areas are fit for cultivation.

Erosion and the encroaching desertification process in the region affect nearly 80% of Loja province. The vegetation is damaged and the number of animals has fallen. Local communities have witnessed a drop in their productivity while the dry periods gradually grow longer from year to year.

The National University of Loja has selected an ingenious way to satisfy the needs of the population during the dry season with the introduction of live fences, which counter the erosion of mountainous lands while protecting crops. This was achieved by introducing drought-resistant nopal crops, a cactus possessing various nutritional and therapeutic effects and which is associated with the exploitation of cochineal, used for centuries in the production of dyes.

Mountainous ecosystems

In Loja province, the only land available for agriculture is found in the Andean valleys at an altitude that varies between 140 metres in the south and 4,000 metres in the north. Due to the mountainous nature of the region, the climate here is extremely variable with temperatures fluctuating between 0°C to 22 °C, whereas the majority of the province benefits from a tropical climate. Generally, the soils of the province are very poor, superficial in depth and rocky in texture. The land used for agriculture has low fertility and is deficient in water content, characteristic of soils that have been subjected to deforestation practices. Without natural vegetation cover to enrich the soils with organic matter that protect them from outside aggressions such as erosion, the soils become barren.

1. By introducing the nopal crop in Loja province,
the National University of Loja created a source
of income for the local farmers while at the
same time, protecting the environment.
© UNEPs Success Stories photo archive

badCauses and effects of population and soil deterioration

In Loja province, land occupation began in 1750 with the arrival of the Spaniards who founded the first villages and began the indiscriminate exploitation of the existing natural resources. From the indigenous population, the settlers learned of the therapeutic properties of the cinchona bark (Sinchona officiales), a native tree of the region containing quinine, the only remedy until the twentieth century known to be effective against malaria.

The use and exploitation of quinine contributed significantly to the deforestation of enormous areas in Loja province, especially in the forests located between 1,500 m and 2,900 m altitude. The quinine produced in Loja was exported throughout the world. Between 1755 and 1758, customs authorities recorded the export of 717,156 kg of quinine. Given that approximately 15 trees are needed to produce 12 kg of quinine, it has been estimated that 900,000 trees were felled in the region over a period of three years.

In the nineteenth century with the introduction of livestock (bovine, ovine, equine) and the development of hillside agriculture, the destruction of the remaining forests was accelerated and the areas converted into grazing pastures and marginal agricultural zones. In most cases, the Spanish settlers neglected the environmental characteristics of the region by using ill-adapted techniques such as ploughing that seriously contributed to soil erosion. The settlers imported the method from Europe without realising that it contributed to the erosion of the terraced hills of Loja province.
Agricultural terracing techniques and other systems used by pre-Columbian communities were also completely ignored. Due to a shortage of flat lands for farming, the planting of crops on slopes or hillsides was introduced, however the necessary measures needed to prevent erosion and provide the irrigation needed for this particular topography, were not taken into consideration.

Clearings and slash and burn techniques also contributed to, and accelerated, the destruction of soil, fauna, water and forest ecosystems. In addition to the destruction of forests, the introduction of goats to these fragile ecosystems soon transformed the region in to an ecological catastrophe.

2. Nopal, or prickly pear cactus possesses fruit
and leaves that have been appreciated by indigenous
peoples for centuries. They are being rediscovered today.
UNEPs Success Stories photo archive

The local population of Loja inherited the damaging practices harmful to local ecological conditions. The results were devastating: advanced erosion and soil deterioration and the loss of fertility were responsible for the constant drop in productivity over the decades, adding to the financial insecurities of the families concerned. As well as effects from human intervention, the long periods of drought that occasionally affected the region, drove the rural population to increasingly migrate to the cities. In the first half of the 1990s, 160,000 inhabitants from the total population of 400,000 left the region.

The agricultural policy reform introduced in 1964 did not achieve the expected results. The majority of the local populations were allocated land of poor quality on the steepest slopes and without the possibility of irrigation. The tendency to over-exploit the barren lands using ill-adapted techniques is hardly surprising.
According to the official 1990 census, 78% of rural workers live in poverty without economic alternatives. During the first months of the year and taking advantage of the scarce rainfall, the farmers plant short cycle crops such as maize, yam, peanut and beans and are left with little or few options for the rest of the year.

goodPossible solutions

Despite the environmental difficulties and the devastating influences of the colonial system of production, the communities of the Loja province have maintained some of the pre-Columbian traditions as well as tried and tested knowledge of local flora and fauna. This traditional knowledge continues to be appreciated by farmers, particularly among the elders who still recognize the source of income it represents during long periods of drought.

3. Cochineal protect themselves by secreting a
white cotton-like substance. From the body of the insect,
a red liquid is extracted.
© Peter V. Sengbusch Hamburg University, Germany

Chief among these is the planting of optunia or nopal (Opuntia ficus-indica), also known as the prickly pear, these fruits have been appreciated by indigenous people for centuries and have persisted up to the present day (picture 1.). This cactus possesses many benefits: its fruits (the prickly pear) are excellent, its leaves are edible in salads or can be used for cattle fodder (picture 4.). Another ancient tradition is the harvesting of cochineal (Dactilopius coccus) a small insect obtained from the nopal and from which indigenous peoples have traditionally extracted dyes. A cotton-like envelope that is filled with a red crimson liquid protects the insects (picture 3.). After collecting the cochineal found on the nopal leaves, they are dried and a pigment is extracted, which is used as a dye for clothing, ceramics and ceremonial ornaments.

bladNopal fences and associated species

In view of the social, economic and environmental conditions, the National University of Loja considered bringing together both the reintroduction of traditional knowledge and the combat against desertification by planting nopal fences and other associated species (picture 2.).
The idea of the project was based on the ancestral harvesting of nopal in the region and the exploitation of cochineal. Not only can farmers benefit from traditional nopal and cochineal products that they consume, but also its reintroduction combats the desertification process. To achieve this, the nopal was grown in the form of live fences and was associated with local drought-resistant vegetation. Planted along the length of small terraces that follow the contour lines, these fences stabilize the soils on the slopes and protect the crops from wind and the effects of erosion.

Since the pilot project sought to be visible by all, it was implemented in strategic locations that were regularly visited by farmers. The live fences should respond to two criteria: the plants should be healthy and vigorous, as they will function as barriers for as long as thirty years, and ensure the production of fruit and fodder. The selected species of nopal should also be attractive to the cochineal, the main source of income derived from the project.

The live fences were installed in an area of 2 hectares in the vicinity of the road linking Malacatos to Vilcabamba, where around 1000 and 800 farmers live respectively. At the time of implementation, the soils were very damaged and showed signs of marked erosion.

4. Nopal, or pickly pear containing many small seeds,
provides round-shaped fruits whose colour varies
between orange and red.
© Peter V. Sengbusch Hamburg University, Germany

The implementation of the project hinged on the following points:

The live fences were planted along the contour lines, the nopal alternating with local flora species that would eventually become a source of firewood.
During the course of the project, Loja University looked to involve the population and local organizations (schools, NGOs, churches). To do this, the person responsible for the project visited the different sectors of the province to identify the ecosystem and discuss the project with the local farmers. Certain members of the community participated directly in the project following demonstrations held at the University, while other groups undertook nopal cultivation and cochineal exploitation supported by other initiatives.


The project of live fences of nopal and associated species has effectively contributed to combating desertification in the province of Loja in Ecuador. The following benefits have been observed:

  • the agro-ecological approach of the project restores degraded land by the construction of fences with nopal and local species, which halt the process of erosion.
  • the production of fruits and fodder from nopal and dyes from cochineal improves the income of the local population, particularly during drought periods.
  • the use of traditional knowledge with the reintroduction of nopal and the exploitation of cochineal, improves the relationship between the local farmers and their economic development.

This case study was proposed by Mr Fernando Casas-Castañeda and Mr Hector Matallo within the framework of the United Nations Environment Programme ‘Saving the Drylands’ award.
For more information, please contact the following person:

Mrs Elizabeth Migongo-Bake
PO Box 30552

Tel. (+254) 2 623252/61
Fax (+254) 2 624249



The teacher tells the story of nopal cultivation
and the exploitation
of cochineal to the class.


Locate the region of Loja in Ecuador.
Is your country on the same continent as Ecuador? Are your problems similar to those experienced by the Loja farmers? What are the differences? What are the similarities?


Draw the prickly pear with
its curved form, its leaves and its large fruits and the small thorns on its leaves and the fruits.


Draw a live nopal fence and other associated species. Paste your picture to your notebook.


Do you know how to extract colour from cochineal to make dyes? Do you know other ways to make dyes from natural products?


Tick the correct answers from the following:

In Ecuador, live fences made of nopal are used to:

• farm cochineal.
• produce firewood.
• protect crops.
• farm prickly pear.
• prick children.
• halt erosion.
• attract rain.


Do you know of nopal or any other cactus whose fruits and leaves can be eaten? Invent a recipe with the leaves and fruits of the cactus in class. If this cactus can be found in your region, follow the recipe in class so that everyone can enjoy it!

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