Cultivation of Neem (Azadirachta indica, Meliaceae) in Saudi Arabia I

SALEEM AHMED, 2 SALEM BAMOFLEH, AND MA'TOUG MUNSHI 3

What is probably the world's largest neem (Azadirachta indica) plantation is on 10 sq km in the Plains o f Arafat, Saudi Arabia, where 50,000 trees have been planted recently. The project, designed to provide shade to the ca. 2 million Muslim pilgrims who camp there annually for "Haj" rites, has economic potential Pest- control materials, soap, toothpaste, and pharmaceutical products are among items that could be produced for home consumption and export. Introduced into the country more than 40 yr ago, the tree has acclimated itself remarkably well to the local hot and arid conditions.

La Culture du Neem (Azadirachta indica, Meliaceae) en Arabie Seoudite. La plus grande plantation de neem (Azadirachta indica) entourne dix kilometres carr~s dans les Plaines d'Arafat, Arabie S~oudite, oft 50.000 arbres ont ~t~s plant,s r~- cemment. Le projet, c r ~ pour fournir ombrage aux 2 millions de p~lerins musul- mans qui y campent annuellement pour les rites de "'haj, "" a potentiel ~conomique. Les articles que t" on pourra produire pour consommation domestique et exportation incluent les materiels pour r~gler des pestes, le savon, le dentifrice, et les produits pharmaceutiques. Introduit au pays il y a plus que 40 ans, l'arbre s'est adapt~ remarquablement bien a la chaleur locale et aux conditions arides.

Probably the world 's largest nearly pure stand o f n e e m trees (Azadirachta indica A. Juss., Meliaceae) is being cult ivated in Saudi Arabia. Fifty thousand trees are being planted on the Plains o f Arafat near Makkah (Mecca) (Fig. 1). Eighty percent o f the task has been accompl ished over the past 4 yr; the remainder , in the next 2-3 yr.

The project, conceived by a Saudi philanthropist , is intended to provide shade f rom the blazing s u m m e r sun for the ca. 2 mill ion "Ha j i s " (Musl im pilgrims) whose annual c a m p here is an essential c o m p o n e n t o f the " H a j " rites. It was f rom a small, approx imate ly 100-m-high hillock called " J a b a l - e - R a h m a t " (Mount o f Mercy), located in the center o f the Plains, that the Prophet M u h a m m a d delivered his farewell se rmon to his followers some 1,400 yr ago. A city o f thousands o f tents springs up annual ly to a c c o m m o d a t e the pilgrims, but these provide little relief f rom the intense s u m m e r heat when Haj, based on the lunar calendar, falls in summer .

N e e m is not new to Saudi Arabia: more than 40 yr ago, mature neem trees were found in a garden in AI-Nakhl M oba rak village near Yenbo on the Red Sea, ca. 200 k m west o f Medinah (Khat tab and E1-Hadidi 1971). Today, in parts o f Jeddah, m a n y houses have neem trees 30--40 yr old. In Makkah, one neem tree is reportedly more than 100 yr old; its seed was apparent ly brought f rom the Indo-

Received 7 November 1987; accepted 6 March 1988. 2 Research Associate and Leader, Botanical Pest Control Project, Resource Systems Institute, East-

West Center, 1777 East-West Road, Honolulu, HI 96848, USA. 3 General Director and Agricultural Engineer, respectively, Agricultural Research Center, P.O. Box

2579, Jeddah, Saudi Arabia.

Economic Botany, 43(1), 1989, pp. 35-38 �9 1989, by the New York Botanical Garden, Bronx, NY 10458

36 ECONOMIC BOTANY [VOL. 43

Fig. 1. Three-year old neem tree on the Plains of Arafat, Saudi Arabia.

Pakistan subcontinent by an immigrant. Scores of other 20--40 yr old trees are found scattered in these two cities and in Madinah, Taif, and elsewhere in the country. Two 20-30 yr old trees are on the Plains of Arafat. In newer urban development schemes in Jeddah and other cities, neem is invariably included in landscaping. It is now probably the most common avenue tree in Jeddah.

The neem tree was chosen to provide the needed shelter at the Plains of Arafat because of the tree's ability to withstand Saudi Arabia's harsh climate. It has acclimated itself remarkably well to local conditions, where temperatures at times approximate 50~ in summer and annual rainfall drops as low as 30--40 mm. Under Saudi Arabia's arid conditions, the tree usually receives some irrigation for about 10-12 yr, after which the tree's deep root is able to tap into the ground water.

Neem thrives under subhumid to semiarid conditions and can be established without irrigation in warm areas with rainfall of less than 500 mm/yr (Ketkar 1976; Radwanski and Wickens 1981). It is, however, killed by frost. Thus, on its native Indo-Pakistan subcontinent, it is found in a large belt extending northwards from Cape Comorin to Delhi and Lahore--from the lush green, high rainfall areas of Kerala to the semi-arid parts of Maharashtra and upper Sind--but it appears to grow best under semiarid conditions. It is also found in Bangladesh, Burma, and Sri Lanka; Indonesia, Malaysia, and Thailand; and Yemen. In Africa, it is particularly widespread in Nigeria and Sudan; occurs along the East African coastal plains stretching from Ethiopia across Somalia, Kenya, and Tanzania to Mozam- bique; and is common in the West African sub-Sahelian region of Mauritania, Togo, Ivory Coast, and the Cameroons (H. Schmutterer, University of Giessen, pers. comm., 1984). In the New World, it is found in Haiti (Lewis and Elvin-

1989] AHMED ET AL.: NEEM 37

Lewis 1983) and Suriname, and is a recent introduction in Cuba and Nicaragua. Nineteenth century immigrants carried the tree from south Asia to Fiji and Mauritius; now it is an integral part of the naturalized flora there and is also spreading to other South Pacific islands. It is actively being introduced in the Philippines, where more than 400 neem trees are now found on the grounds of the International Rice Research Institute at Los Banos, and thousands of seedlings have been distributed nationwide (R. C. Saxena, IRRI, pers. comm., 1987).

PLANTING AND MANAGEMENT AT ARAFAT

Two-year-old neem seedlings are transplanted into 1 m 3 pits. To increase water- holding capacity, the dug-out "soil" (almost pure sand) is mixed with silt (50:50) from a seasonal stream at AI-Husainiyah, about 50 km away. This, however, has some salinity. Better quality silt from Wadi Fatimah (about 100 km away), used previously, is more expensive (250 Saudi riyals or $67 per 5-ton truck compared to 150 SR currently). No chemical fertilizer is applied, but "samad" (chicken manure) is mixed with the soil at 4 kg/tree (reduced from a previous rate of 10 kg, which proved toxic). Neem's extensive roots extract nutrients from deep subsoils, and the tree enriches surface soils through litter. Thus, in northwestern Nigeria, significantly higher total cations, cation exchange capacity, base satura- tion, and pH were observed in soils under neem than in similar soils under fallow (Radwanski and Wickens 1981). Phosphorus, however, was lower under neem, indicating its storage probably in parts other than leaves and twigs.

The trees have been planted 10 m apart in about 90% of the Plains area, and tents to accommodate pilgrims are pitched in-between them. A 5 m x 5 m spacing is used around the Mount where pilgrims observe Haj rites. The impact of these spacings on neem growth and fruit harvest should be monitored as, generally, neem prefers wide spacing. Radwanski (1977), for example, found that a 2 m spacing in Nigeria resulted in tall trees with relatively thin stems.

The trees are irrigated once a week at a rate of 150 L per tree. Water is trucked in from a nearby tubewell dug for the purpose. However, the water's salinity level, as determined at the government's Jeddah & Taif Water Project laboratory (elec- trical conductivity of 4.25 desiSiemens/m and total dissolved solids of 2,763 mg/ L), makes it unfit for drinking and imposes severe restrictions on its use for irrigation. Such restrictions are generally imposed when EC exceeds 3 desiSiemens/m and TDS exceeds 2,000 mg/L (Ayers and Westcot 1985). Cur- rently, however, the trees are doing well, and the earliest plantings are more than 3 m tall (Fig. 1). The sandy soil's high permeability, coupled with a low water table, has apparently helped minimize any salinity buildup in the root zone.

In parts of the Plains, 20,000 seedlings of Ziziphus spina-christi Willd. (sidar), Terminalia catappa L. (myrobalan), and Delonix regia (Bojer) Raf. [Poinciana regia Bojer] (flame tree) have also been planted.

ECONOMIC UTILIZATION

The Ararat plantation could probably be utilized economically. Neem seed oil, cake, and other derivatives (such as kernel powder) could be extracted for pro- duction of pest-control materials, soap, toothpaste, and pharmaceuticals for do- mestic consumption and export (Ahmed and Grainge 1986). The plantation's compact nature will help alleviate the problem in neem fruit collection generally

38 ECONOMIC BOTANY [VOL. 43

encountered in India and Pakistan where neem trees are widely dispersed, often with distances o f more than 50 m between trees (Ahmed and Grainge 1986; Ke tka r and Ketkar 1984). Although labor costs in Saudi Arabia are much higher than those in South Asia, the density o f neem trees in Arabia probably provides a distinct economic advantage.

With the increasing pressure to control the use o f synthetic pesticides, the d e m a n d for safe pest-control products is likely to increase significantly. N e e m mater ia ls have been found to control more than 125 species o f insects, mites, and nematodes - - inc lud ing destruct ive species such as desert and migratory locusts (Schistocerca gragaria and Locusta migratoria), rice and grain borers ( Tryporyza incertulas and Rhizopertha dominica), and termites and nematodes (Reticuli- termes santonensis and Meloidogyne incognita) (Grainge and A h m e d 1988). The same neem materials, though bitter, have been found safe for humans and the env i ronment . Indeed, they have been found to have therapeutic value. Tradi t ional Hindus, for example, eat neem leaves on their new year day for health purposes (Ahmed and Grainge 1986). There is a need, therefore, for an in-depth economic analysis o f the potential profitabili ty of establishing a neem-based industry in Saudi Arabia.

RESEARCH

This a lmost -pure stand of neem also offers a good oppor tuni ty for long- term research on m a n y interrelated subjects, such as: (1) evaluating neem ' s growth and fruit harvest under the prevail ing pedologic and cl imatic condit ions and man- agement practices; (2) assessing N P K and other nutr ient needs for neem tree growth, fruit yield, and fruit quality; (3) es t imat ing the impac t o f the irrigation water ' s salinity level on neem growth and fruit harves t and on the pest-control effectiveness o f neem derivatives; and (4) projecting the impac t o f the neem trees on the area 's microcl imate , microflora, microfauna, and soil properties. Similar studies can also be conducted on the other three plant species planted on the Plains.

LITERATURE CITED

Ahmed, S., and M. Grainge. 1986. Potential of the neem tree (Azadirachta indica) for pest control and rural development. Econ. Bot. 40:201-209.

Ayers, R. S., and D. W. Westcot. 1985. Water quality for agriculture. Irrigation and Drainage Paper No. 29, Rev. 1. FAO, Rome.

Grainge, M., and S. Ahmed. 1988. Handbook of plants with pest-control properties. John Wiley & Sons, New York.

Ketkar, C. M. 1976. Utilization of neem (Azadirachta indica) and its by-products. Directorate of Non-Edible Oils and Soap Industry, Khadi & Village Industries Commission, Pune, India. , and S. M. Ketkar. 1984. Potential of neem oil and neem cake production in India. Paper presented at Res. Planning Workshop, Botanical Pest Control Project, Int. Rice Res. Inst., Los Banos, Philippines.

Khattab, A. B., and M. N. E1-Hadidi. 1971. Results of a botanic expedition to Saudi Arabia in 1944--45. Publ. No. 4, Cairo Univ. Herbarium. Cairo Univ. Press, Cairo.

Lewis, W. H., and M. P. F. Elvin-Lewis. 1983. Neem (Azadirachta indica) cultivated in Haiti. Econ. Bot. 37:69-70.

Radwanski, S. 1977. Neem tree--4: a plantation in Nigeria. World Crops and Livestock 29(5):222- 224. , and G. E. Wickens. 1981. Vegetative fallow and potential value of the neem tree (Azadirachta indica) in the tropics. Econ. Bot. 35:398--414.