Nurse plant effect is a type of plant–plant interaction that can facilitate the focal plant by microclimate modification or protection from herbivory. It also has the potential to affect the community pattern at other trophic levels. I conducted an experiment to examine the potential nurse plant effect by Acacia etbaica on the African perennial woody shrub Solanum campylacanthum. I selected 90 Solanum saplings at the Mpala Research Centre in Kenya, and randomly assigned them to one of three treatments (Thorn, Nonthorn, and Control). In the Thorn treatment, the sapling was covered with branches of A. etbaica; in the Nonthorn treatment, the sapling was covered with branches of Croton dichogamous; and in the Control treatment, the sapling was left uncovered. The stem diameter, total branch length, height, number of leaves, and number of fruits of each plant were measured at the beginning and at the end of the experiment. I also sampled the insects on every sapling at the end of the experiment.
Results/Conclusions
Both A. etbaica and C. dichogamous branches improved the survival and growth rate of S. campylacanthum. Saplings covered by either type of branch also produced significantly more fruits than those left uncovered. However, the nurse plants did not affect the abundance and species richness of insects on the Solanum saplings. My results suggest that nurse plants can improve the performance of S. campylacanthum, but the presence of thorns does not appear to be the reason, since the effect of nonthorned branches of C. dichogamous was indistinguishable from that of A. etbaica.