Hostname: page-component-84b7d79bbc-5lx2p Total loading time: 0 Render date: 2024-07-31T02:30:45.775Z Has data issue: false hasContentIssue false

Clove Tree Yields in the Islands of Zanzibar and Pemba

Published online by Cambridge University Press:  03 October 2008

Peter J. Martin
Affiliation:
Clove Research Project, Ministry of Agriculture, PO Box 159, Zanzibar, Tanzania
Janet Riley*
Affiliation:
Statistics Department, Rothamsted Experimental Station, Harpenden, Hertfordshire, England
Andrew J. Dabek
Affiliation:
Clove Research Project, Ministry of Agriculture, PO Box 159, Zanzibar, Tanzania
*
Correspondence and requests for reprints should be directed to Janet Riley.

Summary

Attention is drawn to the large annual fluctuations of clove yields in Zanzibar and Pemba which appear to result from a synchronization of clove production by trees. Linear regression analyses are presented which show that in years of peak production tree yield is often correlated with tree canopy area and that when trees yield in two consecutive years, yield in the second year is usually negatively correlated with yield in the first year; equations including both variables often leave considerable variation in yield unaccounted for. It is suggested that some of the year to year variation in tree yield may result from an environmental stimulus affecting clove bud differentiation.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1987

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

De Waard, P. W. F. (1974). The development of clove loads and causes of irregular bearing of cloves Eugenia caryophyllus (Sprengel) Bullock et Harrison. Journal of Plantation Crops 2:2331.Google Scholar
Purseglove, J. W., Green, C. L., Brown, D. G. & Robbins, S. R. J. (1981). Cloves, production trade and markets. In Spices, Vol 1, 268276. London: Longmans.Google Scholar
Snedecor, G. W. & Cochran, W. G. (1980). Comparison of regression lines. In Statistical Methods, 385388. Ames: Iowa State University Press.Google Scholar
Tidbury, G. E. (1941). Stem-girth as a criterion in field trials with young clove trees. Experimental Agriculture 11:3339.Google Scholar
Tidbury, G. E. (1949a). The clove trade. In The Clove Tree, 113. London: Crosby Lockwood.Google Scholar
Tidbury, G. E. (1949b). Some recorded yields. In The Clove Tree, 107108. London: Crosby Lockwood.Google Scholar