Exploring Pigeon Valley: An unknown Cryptocarya

This is the 53rd in an ongoing series that highlights the riches of Pigeon Valley, the urban nature reserve in the heart of Glenwood. The focus of this article will be on on an unknown Cryptocarya species.

THE first time I thought about the Cyryptocarya family was when I read in the Economist magazine in 2011 an account of the archaeology of the remarkable Sibudu Cave near Tongaat. Researchers had found the first known use of bedding material by humans – in this case, ‘leaves from Cryptocarya woodii, a tree whose foliage contains chemicals that kill insects. These insecticidal leaves would have discouraged fleas and other biting arthropods – and possibly mosquitoes, too.’ And from a mere 77 000 years ago – in all the debates about land and migration we may ignore just how long there has been human life in this part of the world.

Cryptocarya woodii is certainly found in Pigeon Valley, but there are also two trees of some other species that has not yet been identified. One of these collapsed a few years back, but has since sent up coppices, so its leaves are still visible. The other is larger, but is very exposed to the current digging for the new stormwater piping. There are though a few similar specimens in the area outside the reserve.

ALSO READ: Exploring Pigeon Valley: The Spotted Eagle-Owl

The intriguing problem is that no-one knows what species we are looking at. It could be a hybrid of Cryptocarya woodii and Cryptocarya latifolia, but there are no trees of the latter anywhere nearby. It could be Cryptocarya liebertiana, a species found much further north, but these trees differ markedly from those included in this species. Or it could be a new and extremely rare species, perhaps originating from a hybrid long ago.

That is evidence of the remarkable status of Pigeon Valley. It is not just an unusually diverse urban reserve – it also has rarities that are found in very few other places. It provides access to botanical and zoological information that we may not find elsewhere. For this reason, we oppose any new plantings in the reserve and are determined to protect the biodiversity that is present. This is one reason for the importance of clearing of alien plants, which may otherwise smother rare species. It could be that there are other very rare species that have not yet been identified, adding to the significance of the reserve.

Crispin Hemson chairs the Friends of Pigeon Valley, a group that undertakes clearing of alien plants, keeps records of bird and mammal sightings and alerts management to any problems.

The Friends have a monthly walk at 7.30am on the second Saturday of each month. Email: friendsofpigeonvalley1@gmail.com.

Do you want to receive news alerts via Telegram? Send us a message (not an sms) with your name and surname to 060 532 5535.

You can also join the conversation on Facebook, Twitter and Instagram.

PLEASE NOTE: If you have signed up for our news alerts you need to save the Berea Mail Telegram number as a contact to your phone, otherwise you will not receive our alerts

Here’s where you can download Telegram on Android or Apple.