Over the last few months Richard Boon has been working with Braam van Wyk on the genus Dovyalis and in the process had corresponded with us to get access to collections of this genus in the Hugh Nicholson/Tony Abbott (PCE) herbarium at Umtamvuna Nature Reserve. We then arranged a meeting at the herbarium so he could look at all the Dovyalis vouchers but in particular he was interested in Dovyalis lucida as some of the specimens seem morphologically different from many others he has seen. He and Errol Dowes from Ethekweni Municipality joined us on a crisp and bright winter morning. We spent a little time going through the vouchers and Richard renamed a few of them for us.
We were then joined by Anne, Debbie and Tracy and we set off to Manilkara meander where we had previously collected Dovyalis lucida along the cliff line as Richard wanted to get a feel for these plants in the field. As we walked along we kept our eyes open for other interesting plants. We found a single Homalium rufescens flowering and several Petopentia natalensis in bud.
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| Homalium rufescens |
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| Petopentia natalensis buds |
We then found the first of the Dovyalis lucida trees and Richard could get a good look at the giss of the plant. We looked very carefully for spines on the branches and any serrations on the leaves, common features of Dovyalis. There was also a hunt for coppice growth as these characters are frequently exaggerated there. We failed to find any such features on any of the first few trees we inspected and it was only when we had looked at about 30 trees that Richard found a leaf with a single serration and one or two spines on a stalk. Subsequently we found another, larger tree with several spines on the trunk. However spines seem to be present on fewer than 5% of the trees examined in this sub-population.
Unfortunately none of the trees showed any signs of flowers or fruit as it was probably still a bit early. This means further visits in the next month or two to ensure we can collect sufficient material for Richard to study to verify if this sub-population of Dovyalis lucida is consistent with collections from elsewhere or whether this might be something different.
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| Spines on the trunk of Dovyalis lucida |
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| Leaves on Dovyalis lucida |
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| A cluster of Erica cerinthoides |
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| Looking down into the Umtamvuna River gorge |
Participants: Anne S, Debbie K, Errol D, Graham G, Kate G, Richard B, Tracy T.
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