A pilot study of the breeding system of Henry’s St Jon’s wort
Carryn Smith (University of KwaZulu Natal) and Ingrid Nanni (Invasive Species Programme, SANBI)
Henry’s St Jon’s wort,(Hypericum pseudohenryi) is an invasive alien plant found in the KwaZulu-Natal Drakensberg and Midlands that has been perceived as a threat.
This species can invade watercourses and undisturbed veld. As it is widely established, it was expected that the plant is able to self-pollinate with a large degree of success.
Pollinator exclusion experiments were conducted at three study sites in the Drakensberg and Midlands.
There were three different treatments: emasculated flowers, hand pollinated cross-pollination, and bagged flowers to exclude pollinators and encourage self-pollination.
The results show that while plants are able to undergo self-pollination and produce seeds, the number of seeds produced through self-pollination was significantly lower than the control samples, which were chosen at random on plant.