COMPARISON OF THE GROWTH AND YIELDING OF CLOVE TREES UNDER DIFFERENT RING WEEDING AND FERTILIZER REGIMENS

Clove tree vegetative growth and yields were significantly improved by herbicide ring weeding compared with hand hoeing ('jembe' ring weeding). With jembe ring weeding, tree growth was not appreciably improved by using a larger ring weeding circle than normal. In non-intercropping situations, the application of nitrogen fertilizer or the use of herbicide ring weeding helped to prevent the appearance of the juvenile decline condition in young trees and increased tree yields. Nitrogen and phosphorus fertilizers stimulated weed growth and this was much better controlled by herbicide than by jembe ring weeding. The better weed control with herbicide ring weeding apparently made more of the applied fertilizer available and estimates of clove yields suggested that the maximum response of trees to nitrogen fertilizer occurred at a lower level with herbicide than with jembe ring weeding. © 1990.