Item Details

Title: Honeybee, Apis mellifera (Hymenoptera: Apidae), leaf damage on Alnus species in Uganda: a blessing or curse in agroforestry?

Date Published: 2002
Author/s: P. Nyeko, G. Edwards-Jones and R.K. Day
Data publication:
Funding Agency : Norwegian Agency for International Development (NORAD)
Copyright/patents/trade marks:
Journal Publisher: Bulletin of Entomological Research
Affiliation: National Forestry Resources Research Institute - NaFORRI, 1Faculty of Forestry and Nature Conservation, Makerere University PO Box 7062, Kampala, Uganda: 2School of Agricultural and Forest Sciences, University of Wales, Bangor, Gwynedd, LL57 2UW, UK: 3CAB International, Africa Regional Centre, PO Box 633, Village Market, Nairobi, Kenya


It is a dictum that Apis mellifera Linnaeus is innocuous in agricultural ecosystems. This study provides the first record of A. mellifera as a significant defoliator of Alnus species. Careful field observations coupled with microscopic examination provided convincing evidence implicating A. mellifera as the cause of leaf perforation on Alnus species in Uganda. Apis mellifera was observed foraging selectively on young Alnus leaves and buds in search of a sticky substance, apparently propolis. In so doing, the bee created wounds that enlarged and caused tattering of Alnus leaves as they matured. Biological surveys indicated that the damage was prevalent and occurred widely, particularly on Alnus acuminata Kunth in Uganda. Incidence of the Apis mellifera damage on Alnus acuminata peaked in the dry season, with up to 90% of leaves emerging per shoot per month damaged, and was lowest in the wet months during peak leaf emergence. Apis mellifera leaf damage was consistently higher on Alnus acuminata than A. nepalensis D. Don., on saplings than mature trees, and on sun exposed than shaded leaves. The activity of honeybees may be detrimental to the productivity of Alnus, yet the substance for which the insect forages on Alnus is a resource with potential economic importance.