The Neem Tree

Orientation "Neem"

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"Poverty is not necessarily the want of money or cash in hand. In a wider sense it is the lack of option, whether it is the none-availability of fertilizer for crop cultivation or pesticides for crop protection, medical remedies for family welfare, safe contraceptives for regulating family size, fuel or firewood for cooking, timber for furniture or dwelling, or the availability of appropriate technology for restoring wastelands, or absence of income generation and employment opportunities. In all these respects, Neem could be a 'panacea', particularly in rural areas."

Dr. Saxena, Chairman of the Neem Foundation [Neem Foundation, 1997-2]

Description of the Neem Tree (Azadirchata indica)

Its blossoms are small, white flowers with a very sweet, jasmine-like scent. Its edible fruit  — loved by children in Africa — is about 3/4 of an inch (2 cm) long, with white kernels. A neem tree generally begins bearing fruits at three to five years of age, and can produce up to 50 kg (110 lbs.) of fruit annually when mature. The pinnate leaves have a very bitter taste and a garlic-like smell. (See the picture of a leaf.)

Due to its medical and insecticidal properties, the neem tree has been widely used in the traditional medicine and agriculture of India. Apart form Azadirchata indica there are two other know species of neem: Azadirachta siamensis and Azadirachta excelsa. [MotherNature, 1999; Neem Company-3]

Young Neem Trees in the Surroundings of Tamale (Ghana)

Azadirachta siamensis

Azadirachta excelsa

History of Neem

With the advent of Europeans on the Indian subcontinent, the religious practices around the neem tree were stigmatised as heathen practice and over time most practical uses were abandoned. However, at the beginning of this century the neem tree was still highly estimed by Indian emigrants and they took it along to the places were they settled. Thus, the neem tree was introduced in places like Australia, East and sub-Sahelian Africa, South East Asia, and South America. In Indian agriculture, neem cake (the remains from the oil production out of neem seeds) was in use as a fertilizer and pesticide in sugar cane fields up to the 1930s.

With the end of the colonials era, interest in the neem tree was on the rise again. Pioneering work in the possible commercial use of Neem oil and cake had been done by the Indian Institute of Science in Bangalore as early as the 1920s. Recalling the insecticidal properties of neem, researchers began programs in the early sixties to identify the active principles and screen them against major crop pests. Several active ingredients were isolated from various parts of the tree, among them meliantriol and azadirachtin.

In the last two decades research on neem has been intensified and many of the trees agricultural and medical properties were rediscovered. Today, neem plays a major role in the rural industry of India and projects for the commercial use of neem have been successfully introduced in such places as Kenya. [MotherNature, 1999; Neem Company-5; Neem Foundation, 1997-2; Neem Foundation, 1997-3]

A Closer Look at the Neem Tree

Active Ingredients

Single Leave of a Neem Tree

Producing Neem Extracts and Oils

In many areas the neem seeds are easy to collect from the ground because bird or fruit bats eat the juicy and sweet fruits and spit out the kernels. If this is not the case the harvested ripe fruits need to be pulped. If water is available, the kernels should be washed to minimize the risk of fungal infection. Fur further processing and storage, the kernels should be dried well. This is best done by spreading them on the ground in the sun. To avoid moulding, the kernels should never be stored in a plastic bag.
 

Seeds for planting  If kernels are sowed immediately, they do not need any treatment. However, seeds for later planting must be carefully dried in the shade. Temperatures above 45° C or storage for more than one month will reduce germination.

To press neem oil by hand, the kernels have to be crushed first in a big mortar, like the one used for "fufu". — As neem seed are very bitter, a separate mortar should be used. — Then the shells have to be removed by winnowing as is done with cereals. Now the kernels can be ground in a mill or pounded in a mortar. The resulting powder should be moistened with a little bit of water (not too much) until it sticks together and an almost solid ball can be formed. This dough should be kneaded for several minutes until oil collects on the surface. If this is the case, the oil can be pressed out in drops by firmly pressing the dough. By alternatingly kneading and pressing half of the oil in the kernels can be obtained which can amount to 100 - 150 ml per kg.

If an oil press is available, the work can be simplified and the resulting amount of oil increased. Heating of the oil will not affect its insecticidal purpose. [Neem Company-5;  Neem Foundation, 1997-1]
 

Neem oil production in brief  A) Preparation 1. Gather the fruits and pulp them to  remove the flesh  2. Wash the kernels if possible to avoid fungal infection  3. Dry the kernels in the sun as done with rice or fish  B) Oil pressing 4. Crush the kernels in a fufu mortar (because of the bitter taste, use a separate mortar)  5. Remove the shells of the kernels by winnowing, as done with cereals  6. Grind the kernels in a mortar until a powder is obtained  7. Moisten the powder with a little water and form a dough-ball  8. Knead the ball until oil collects on the surface  9. Press the oil out.  10 Repeat steps 8 and 9 until you obtain about a third to half a small bottle of oil per kg of crushed kernels

How the Neem's Products are Used

Use of Neem in Malaria

Because the anti-malarial effects of neem appear to be greater in the body than on the petri dish, there has been some speculation that stimulation of the immune system is a major factor in neem's effectiveness against malaria. In addition to its anti-malarial activity, neem also lowers the fever and increases the appetite. Thus, strengthening the body and speeding recovery. [icipe, 1998-2, S. 187; Neem Foundation, 1997-1; VillagePharmacy]
 

Malaria Prevention  Drinking neem teas or chewing a couple of leaves every day reduces the possibility of contracting malaria. Extracts obtained by a water and acetone combination are even more effective than plain neem tea. [Neem Company-1]  Malaria Treatment  Boil 30 g of neem leaves in 3 liters of water for 20 minutes and take one glass of this leaf extract three times a day for one week. (This treatment has been successfully used in the Wamirithu Herbal Clinic in Kenya. Patients were cured completely within one week.) [Neem Company-3]

Use of Neem as Insect Repellent

Use of Neem as Insecticide

The most commonly used products in pest control are extracts from seeds or leaves. The seeds have about twice the potency of the leaves, but they are only available for 3-4 months each year. Leaves have to be dried in the shade, because the sunlight will break done some active ingredients. The powder obtained from crushed leaves can be used directly for dusting crops or as powder in stored foods. It can also be mixed with water on sprayed on crops. If the kernels are used they should be soaked in water overnight. The extract can be filtered and applied by a hand-pump sprayer. As the active compounds of neem decompose rapidly, drops under attack have to be treated weekly. [Neem Company-5]
 

Water Extract for Plant Protection  A) First Day 1. Prepare the mixture: 25 g of peeled and grounded neem kernels or 50 g of grounded neem seeds per liter of water.  2. Let the mixture stay overnight.  B) Second Day 3. Filter the extract through a fine gauze, meshed sieve or tissue to remove bigger particles.  4. Apply the extract with a knapsack or hand-pump sprayer weekly. [Neem Company-5]

Other Uses of Neem

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