Cobra Lily research study
At the beginning of May the NVT research team found a cobra lily, Chasmanthe aethiopica, flowering outside the office. The team decided to do some research on this particular plant and went on a search around Nature’s Valley to see if there were any more flowering in the area and we found a number of little populations growing. Chasmanthe aethiopica is a lily which can be found flowering along forest margins and coastal dunes. It belongs to the iris family (Iridaceae) and has a flowering period between April and July. The plant has a number of tube flowers, orange in colour, which grow along an unbranched spike and the leaves are soft in texture and sword-like.
For this study we are looking at the pollination of the cobra lily to see if it capable of self-pollination and whether or not it is solely dependent on sunbirds for pollination. To do this we placed cages over five different plants to prevent sunbirds from accessing the flowers but still allowing insects access. This will allow us to determine whether the cobra lily needs the sunbird for pollination or if insects are capable of pollinating the flowers as well. We then placed soft fabric bags (so not to damage the flowers) over the flowers of another five different plants. This prevents any birds or insects from accessing the flowers and will help us determine whether or not Chasmanthe aethiopica is capable of self-pollination.
Every day for the duration of the flowering period we took nectar measurements from one flower for all the caged and bagged plants as well as for five open plants. Flower measurements were also taken from the flowers which we took nectar from. This will help us determine how much nectar is produced on average when the flowers are not visited and what happens when they are.
The team then went around Nature’s Valley and took the GPS coordinates of all the flowering cobra lilies and recorded the number of flowers on each plant and which of those were in flower (open flowers) or in bud (closed flowers). Once the cobra lilies finished flowering we then removed the cages and took the fruit from those plants so that we can dry them and count the seeds. We did the same for the plants which were bagged and also for five plants that had neither a cage nor a bag. We then went back around the Valley to see how many fruit sets each of the plants had produced to see if there are any difference between the small populations around the Valley.
Once the fruit has dried and we are able to count the seeds we will be able to hopefully determine how much the cobra lily relies on sunbirds for their pollination and whether or not they are capable of self-pollination. This will form one of our long term studies and will be repeated during the flowering period again next year so we can learn more about this pretty species of lily. Some exciting results to discover in the near future for this study :-)