Recent investigations have shown that the juvenile decline condition is widespread amongst young clove trees in Zanzibar and Pemba and causes a serious loss in production. In the past the condition, which affects young clove trees on both islands, has been attributed to pathological or agronomic causes. Results are presented which show that trees affected with the condition respond very favourably to the use of herbicide for ring weeding and the application of the fertilizer ammonium sulphate. It is suggested that juvenile decline is caused by weed competition for nitrogen; the role of other factors in contributing to the condition is discussed.