MesembsVirtually – Insights into the Evolution of Mesembs

With Derek Tribble
Sunday, October 15, 2023 – 11:30am Pacific Time (California), 7:30pm BST (UK),
Your local time may vary. Watch on Zoom at this link. or on Facebook Live

MesembsVirtually is a quarterly Zoom lecture series sponsored by the San Francisco Succulent & Cactus Society, the Manchester Branch of the BCSS, and the Mesemb Study Group.

If you are looking for SFSCS October 17 meeting info, go to – Troy Stephens – A Tour of Oaxaca


Program Description

It is widely known that no fossilised succulent plants have been discovered, presumably because they inhabited dry places. But within the family containing Mesembs, many plants that are thought to resemble ancestors are still living around the world today. It needs a close look to realise their relationships.

This presentation begins by setting the scene for diversification of Mesembs. The major winter-rainfall vegetation types of South Africa are briefly described (Fynbos & Succulent Karoo). An understanding of these areas also gives lessons for cultivation. How do Mesembs manage to dominate the landscape in places? Important characters linked to their successful diversification are indicated as the plants became larger, storing more water in a drying landscape. But succulents also have an unusual capacity for miniaturisation, leading to the evolution of tiny plants suitable for pot cultivation e.g. Conophytums.

Derek Tribble from London has been growing cacti and succulents continuously as an amateur since his teenage years in the 1960’s in the UK. After sixteen visits to South Africa to photograph plants in nature, his passion now is studying & giving presentations about leaf succulents. Among other roles, he is currently chairman of the Mesemb Study Group.

Watch on Zoom at this link. or on Facebook Live.


And don’t miss our October meeting – “A Tour of Oaxaca”

With Troy Stephens
Tuesday, October 17, 2023 – 7:00 pm Pacific Time (California)

Members and visitors can attend in person in San Francisco,
or register/join the meeting in progress on Zoom.


Program Description

Join us as Troy Stephens presents highlights from his recent adventure to the botanically rich state of Oaxaca, Mexico. We’ve had more than a couple of presentations over the years on Oaxaca, and for good reason. There probably isn’t another place in North America with a higher rate of biodiversity and density of ecotypes. With everything from summer monsoonal desert basins, to cool and moist cloud forests, Oaxaca is full of almost any kind of plant you can imagine; from palms and cycads, to ferns and aroids, and of course cacti and succulents.

Troy had the opportunity to explore the northern part of the state and observe a selection of the peculiar plants that grow there. His presentation will be from the perspective of someone getting out into the field for the first time. With a few of his plant buddies crammed into a tiny SUV, he spent two weeks clambering through the mountains and tiny pueblos with a long list of species to search for. 

Troy is a plant grower, collector, and enthusiast from Alameda, CA and has been growing succulents and other plants for quite some time now. He is a manager and plant buyer at the Grand Lake Ace Garden Center in Oakland, a perennial volunteer at the Gardens at Lake Merritt, and one of the Board Members of our society. Aloes, succulent bulbs, and caudiciform succulents represent a significant portion of what he likes to grow and collect, but not unlike many of us, he grows a little bit of everything.

Show & tell table: Adromischus on the succulent side, and Ariocarpus on the cactus side (plus other hard-tubercle Mexican cacti such as Obregonia, Strombocactus and Pelecyphora)

Featured grower: Carl Frederick

Snack table:, There will be a shared spread, but we suggest bringing something every couple of months if you partake regularly. As a thought, we are often short on drinks. 

Covid precautions: Vaccination recommended. We will keep doors open to ensure adequate ventilation. This can make the room a bit chilly so dress appropriately.

Meeting Agenda

7:00 Mingling and announcements
7:30 Formal presentation starts promptly with Society business
7:35 Show and Tell Table
7:50 Leg stretch
7:55 Featured presentation


Watch Online

On Zoom: Register or join the meeting in progress.

Or watch the simulcast on our Facebook page: http://fb.me/sfsucculent


Upcoming Events

Meetings usually on the third Tuesday each month

  • October 15 (Sunday) – MesembsVirtually Quarterly Zoom Broadcast – Derek Tribble – Insights into the Evolution of Mesembs. (Zoom Only. 11:30am California time, on a Sunday)
  • October 17 meeting – Troy Stephens – A Tour of Oaxaca
  • October 28 (Saturday) 10am-2pm- Plant Swap & Multi-Society Showcase

SFSCS will have a table at this event near the entrance of the SF Botanical Garden in Golden Gate Park. Meet and mingle with other society members, browse selections from our library.

Tickets are $35 – includes access to the rest of the Botanical Garden. Enjoy pie and seasonal drinks, plant swap, games and giveaways.

The event is produced by Seed and Soul Plant Club and the Botanical Garden Society – More info and registration


  • Upcoming events, continued…
  • November 21- meeting – Jeremy Spath on his new Dudleya Book
  • December 19 meeting – Solstice Party (potluck with gift exchange)
  • January 16 meeting- 2024, Pam Koide-Hyat on Peru
  • April 2024 – Jeff Moore – Author of several books on succulents