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In search of a soft chemistry for desert locust control, botanical insecticides have been shown to be highly effective against locusts and to be non-toxic to mammals and birds. They are environmentally friendly due to their complete degradation in the soil. Biologically interesting limonoids have been identified in tropical Meliaceae, like Azadirachta indica (neem) or Melia volkensii. The latter has only been found in East Africa. Each tree is capable of yielding 100 kg of dry fruits per season, from which about 1 kg of a highly active powder can be produced. Field tests have shown that the crude powder in a dose of about 10 g ha(-1) gave effective control. The effect results from acute toxicity (28%), retarded growth and an 80% rate of malformations, First results from a technical-scale production of M. volkensii powder are presented.