In Zanzibar, East Africa, trunk injection techniques are being used to investigate the aetiology of sudden-death disease of clove trees, Eugenia caryophyllus (Sprengel) Bullock and Harrison. A low-pressure trunk injection system is described which has proved itself capable of frequently injecting 5 / of solution into trees in less than 1 h. Uptake rates for injections using two different designs of injection nozzle and different chemical solutions are presented and compared.