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Central American University - UCA  
  Number 158 | Septiembre 1994
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"NIM": Nature's Own Insecticide

No laboratory in the world has managed to create an insecticide as selective, as original and as respectful of life as the one that is found hidden in the yellow fruit of the neem tree, a plant that already has Nicaraguan citizenship.

Raquel Fernández

When the Green Revolution, with its aggressive and short term agricultural production methods, spread throughout the world, it promoted a negative concept of insects. Peasants who work the land daily with their own hands, however, knew that not all insects are bad. In reality, only 5% of them damage plants by eating them. The rest are beneficial or innocuous. In the long run, all insects, even the damaging ones, are beneficial when they die, because they fertilize the earth.

But the technicians, who learned everything they knew about the land in libraries, laboratories or experimental plots, imposed their criteria. And the Green Revolution advanced, accompanied by huge quantities of insecticides and pesticides, which even today, despite their poisonous effects, are still a succulent business for 10 chemical transnationals.

Poison, Destruction, Still More Poison

Chemical insecticides are a calamity in various ways. They reduce the whole insect population, both damaging and innocuous, in drastic measure. Those who build up a resistance to their effects for some reason, only the damaging 5% become stronger and more voracious. With their new strength and their competitors killed off, they multiply much more quickly than is normal in the species.

Years and years of indiscriminate chemical use has created a vicious circle; the insecticides must have stronger and stronger concentrations of poison to overcome the resistance of the insects, which, in turn, adapt, resist more and become even more destructive.

Agriculture obviously needs mechanisms to control damaging insects. The ideal would be a selective insecticide that only affects those that eat the crops. It would be even better if that insecticide could work in a way that would not damage the crops, but could fertilize the soil. And best of all would be if that insecticide were not also harmful to human beings, domestic animals, plants and fruits, air and water.

No laboratory has achieved this. But Nature herself has created, for those human beings that treat her so badly, a tree that provides an insecticide fulfilling all of these demands with no negative effects: the neem.

From India to Nicaragua

The neem tree, phonetically spelled nim in Nicaragua, grows 16 to 20 feet in height, with small bright green leaves and conically shaped yellow fruit clusters that bloom through the foliage. It could be an ornamental plant in any garden because of its beauty and uniqueness.

It comes from India, its scientific name is Azadirachta indica A. Jus and it belongs to the Meliáceas family. As with almost all trees originally from India that are now found around the world, the nim's geographical extension is thanks to the mobility of the soldiers that maintained the British empire.

The nim did not find its way to Nicaragua through military means, however. In 1975, a group of British researchers planted small experimental plots to study the tree's adaptability to our climate. They abandoned the project in 1979, after the revolutionary triumph, but the then new Institute of Natural and Environmental Resources (IRENA), immediately took it over.

The experiments continued and the conclusion was reached that the nim could effectively adapt to Nicaragua. It survives droughts, helps control soil erosion, offers good shade, and is capable of creating a fresh and green microclimate in particularly dry and arid zones. When its leaves fall, they decompose and help the most starved soils recover minerals. It has good quality wood that can be used for furniture when old trees are cut down to make space for younger ones. The branches can also be used for firewood during the annual thinning process.

A Three Pronged Attack

The nim is a complete insecticide. The active substance is present in the whole tree, but is concentrated in the seeds. The nim's insecticide is very complex and acts simultaneously in three directions against damaging crop eating insects.

As a repellent, the nim serves to drive away certain insects. But this is not its most important function.

The nim is also a phagodeterrent: it arrests the growth of damaging insects. Insects eat plants treated by the nim insecticide, and even appear to find them more appetizing. But at a certain point in their digestive process, the insects, still at the voracious larva stage, begin to eat less and less, until they stop eating and die, before reaching sexual maturity. The damage caused to the crops by what the insects did eat can be viewed as an investment to reduce the pest population in future generations.

The third and most interesting form of the insecticide's actions is its attack on the damaging insect's hormonal system. The insect develops perfectly throughout all of its stages, apparently unaffected. The problems begin with breeding. It simply cannot. Small physical malformations prevent it; a wing that did not grow correctly, a longer or shorter leg, lack of sexual appetite, sterility. With no breeding, there are no baby insects, and the damaging insect population is reduced from generation to generation.

The nim's active ingredient is azadirachtina, whose chemical composition is so complex that the most sophisticated chemical laboratories have not been able to synthetically produce it, although research has been going on for a number of years.

Homemade Insecticide

More and more Nicaraguan peasants are planting nim trees in their yards to protect their crops. Caring for the nim is not complicated. The tree is not very demanding and accommodates to almost any circumstance, although it should be planted in a nursery. It has one characteristic that must be noted; it is a species that rapidly occupies all available space.

The nim grows rapidly. In its third year the first fruits can be used for cottage production of the insecticide. The task is simple: 13 lbs. of cleaned and dry seeds are ground, wrapped in a clean cloth and put in water. Twelve hours later, the cloth is tightly pressed to release as much of the substance as possible. In another container, 10 grams of bar soap for clothes (not detergent) are dissolved, then added to the extract. Enough water is then added to make 100 liters. Ready to fumigate. Naturally, the quantities vary depending on the area that will be fumigated.

The World's First Nim Factory

The success of nim insecticide on small farms, where the farmers themselves make the product, was the source of the idea to produce it in large quantities of standard quality for commercial presentation. The Nim Insecticide Production Cooperative (COPINIM) was founded in Managua in 1987, with 12 members.

It is one thing to manage a dozen nim trees in one's backyard to fumigate small farms, and another to develop an industrial plant, even if of modest proportions. And there was no previous experience of a nim factory nursery to draw on.

The members of COPINIM faced the challenges and new problems with energy. Seven years after the first plantings, the nim forest, which needs no irrigation, extends for 70 hectares and annually produces between 20 and 25 kilos of fruit per tree in two harvests, which begin when the tree is three years old and stabilize at seven.

The nim has only two natural enemies. Locusts like to eat the young leaves, which do not have enough insecticide to kill such a large insect. Large ants called "zompopos" carry the leaves to their nests for fermentation, together with other leaves, which serves as their food. Since they do not eat the leaves, they do not get poisoned. Mechanical procedures are used to chase away both pests or make it more difficult for them to access the tree.

Pickers and Selectors

The first and most important of the nim's two yearly harvests comes in the June August period. The second, which is not as reliable, and must be watched for so as not to miss it, is between December and January.

During the harvest, above all the first one, the processing plant shifts gears because of increased labor demands. The picking brigades collect the ripe fruit as well as those that have reached their full growth but are not yet quite mature. They also trim any branches that are taller than three meters, to make sure the tree's fruits are always reachable and to improve production the following year. The nim forest thereby produces a good supply of firewood that benefits both the tree and those who use it, since the tree grows better when trimmed.

The selection teams at the plant separate the ripe seeds from the unripe. This temporary employment gives jobs to between 25 and 80 workers, depending on the harvest. The work is very delicate, and only women do it. The unripe fruits are put in special areas, with good ventilation and shade, until they are fully ripe, which generally takes a week.

The first step of the industrial process itself consists of washing the fruits. During the first harvests, for lack of a better machine, the COPINIM members washed the fruits in laundry machines on the gentlest cycle. But the work went much too slowly given the size of the harvest, so local engineers developed a specific machine for this task that can wash up to five tons daily.

The machine separates the pulp from the seed, taking care that the seed is thoroughly cleaned. The pulp is composted into organic fertilizer to be used in fertilizing the nim trees. It is not just any fertilizer; nim based fertilizer carries the insecticide with it, and is especially effective against damaging insects that live in the soil and eat plant roots, such as nematodes.

Once separated from the pulp, the seed is put in the sun for three or four hours for pre drying. Later, in a shady spot the insecticide substance is sensitive to heat the drying is continued for 20 days or more, depending on humidity levels in the seed and the environment.

The Industrial Insecticide

When the seed contains less than 9% humidity, it is ready to have the insecticide extracted. A modified coffee thresher is used to de shell the seed. The shell is then ground into a powder that serves as the base of the nim insecticide in certain dry applications and strengthens its action.

Three different products are obtained from the totally clean seed. The ground seed, commercially known as Nim 20, is dissolved in water. Nim oil, which comes from pressing the seed, is used in its pure form in a medicinal skin soap, and mixed with emulsions is the CE 80 insecticide, which is also dissolved and applied in small drops. This product is the only nim derivative with any level of toxicity because of the emulsifying ingredients that must be added to it to be used in agriculture, but its danger to human beings cannot be compared with that of any other commercial insecticide. Finally, there is Nim 25, which comes from grinding the pressed seed that remains after extracting the oil. This product can be applied dry or dissolved in water, depending on the crop and the objective. It is recommended to mix it with the ground shell, although sand or sawdust can also be used.

All three products perform the three actions of the nim insecticide; they all repel, stunt the insect's growth and affect reproductivity. The emulsifiable nim sticks better to the insects' respiratory orifices, which provokes asphyxiation. Because of sensitivity to the sun's heat, the three substances should be applied to crops early in the morning or at dusk. When the farms are very large and the insecticide must be applied with airplanes, adequate complements to nim must be designed.

The industrialized nim has shown itself to be an excellent insecticide on small and medium farms and plantations. A lower quantity is needed than conventional insecticides, the applications are spaced farther apart, and the fruits, vegetables and other products harvested can be consumed with no danger, because it is not toxic to human beings. Good prices and high demand for these organically produced products make the nim insecticide even more attractive to agro-exporters.

The COPINIM members offer the insecticide products at favorable prices, without seeking excessive earnings. Their goals are not profit, but rather a dignified life that respects nature.

"We want to offer Nicaragua's peasants a solution to the pest problems that is favorable both to the crops and to their pockets," explained Manuel Moraga. "We produce to sell at favorable prices. And we also buy nim seeds from those who have some trees on their farms and have excess production."
Due to the shortage of money in rural areas, they frequently use the barter system; they pay for seeds that are brought to the plant with developed insecticide.

Nicaragua: First of the First

Nicaragua is at the forefront of nim development, opening the way, accumulating experiences. These experiences provide it with the ability to sell technology.

COPINIM has the most advanced plant that exists today for treating nim seeds and producing insecticide. Its technology and industrial development are constantly being perfected through the design and fabrication of new and better machinery.

Research continues with support and financing from Germany's UNVERTAILEN Foundation, Bread for the World, also from Germany, and Land of the Future, from Sweden. The quality of the COPINIM product, with none of the publicity or dirty dealings of "captive markets" that the contaminating transnational companies so love, has made nim so famous throughout Nicaragua that demand now outstrips supply. Its fame has extended beyond national borders and requests are coming from far away, with tempting offers in dollars.

But the members of this unique cooperative do not listen to that siren call. "The first priority is to satisfy national demand and free our country from the use of poisonous insecticides," says Moraga. "Once we've resolved our own problems, we can trade the surplus internationally. But not now, because if they buy our entire production, we would have to return to poisonous insecticides. We're willing to share our technology with others, but the first task is to solve the problems at home."

Gringos Want to Patent Nim

Both Nicaraguans and Indians are alert. For years, northern transnationals have been "patenting" plants and animals whose properties interest them for experiments and business.

The patent mechanism is the most recent chapter in the story of the South's pillage by the North. It works likes this: a foreign biologist comes to a peasant community in a poor country. The peasants share with the outsider all of the ancestral knowledge about the properties of a plant or an animal that they have gathered over generations. When the visitor returns home, he expresses his appreciation to the host country by patenting the plant or animal and all the information he learned from others. Once the patent is set, no one else can do research on the plant or animal or use it bio technologically without paying "author's rights" to the patentee. The world market has effective legal and trade mechanisms to guarantee the security of the patent.

This is beginning to occur with the nim. For generations, India used the nim as an insecticide. Now, the W.R. Grace company, a US firm, has patented a modified version of the insecticide, and is promoting it in the United States as "organic insecticide."
The grassroots movement in India has initiated a campaign to contest W.R. Grace's right to the product patent. Among other actions, more than half a million farmers protested in Bangalore on October 3, 1993, demanding protection for "sovereignty over our seeds," and "communal property rights."

A Suspense Story

We will finish with a typical story. Once upon a time a cooperative called San Gabriel, near La Paz Centro, Nicaragua, was dedicated to sesame and soy production. One fateful day in 1992 the peasants discovered that their crops had been attacked by a plague known as the "chinche de mancha," or "stained bug." They decided to apply the nim insecticide with the help of engineer René Marín, at that time a member of the cooperative and now working in CIPRES, a nongovernmental organization that also promotes nim.

After many years of working according to the dictates of conventional agriculture, the peasants were accustomed to seeing the ground covered with dead insects the day after applying a chemical insecticide. This did not happen with the nim. When the peasants went to see their crops the next day, they found the bugs hopping from leaf to leaf, full of energy.

As the days passed, there were more bugs with more energy. "We were desperate," remembers René Marín. "This plague is considered very dangerous to crops when one bug is seen for every lineal meter. We had up to ten."
Only one thing that kept the peasants from forgetting their recent ecological awareness and returning to conventional agriculture was that they had no money for chemical insecticides. The decisive reason for choosing nim had been that it was less expensive. And that was why they stayed with it.

Until harvest time. They collected the sesame and the soy and took them to be sold, calculating that, if they were lucky, only half the crop would be damaged. Normally, with a harvest produced by conventional means, a good harvest includes 15% damaged crops. So the peasants were shocked when they were told that only 13% of their crops were damaged.

What had happened? The nim had acted like a product "made by nature." It respected life, all life; that of the bugs and that of the crops. The bugs continued to live, but did less damage. That was the secret, together with the fact that fewer would reproduce.

"I would recommend that, together with the nim insecticide, large doses of tranquilizers are given to the peasants, at least the first time," jokingly suggested René Marín. He is convinced that nim is one answer, but based on his experiences it is not the only one.

All insects are capable of developing effective defenses against any insecticide in the course of a few generations. It is thus necessary to continue looking for new, more and better ways to protect the crops, including crop rotation, alternating plants in the same plots so one will defend the other, biological pest control, and using nim and other natural insecticides still to be researched. All procedures should focus on protecting the crops, but without altering the delicate balance of life. All life plants, animals and human beings are called to live together harmoniously on this marvelous blue planet.

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