IBSA Symposium 2003/Vist to South Africa TOW
Mary Sue Ittner (Mon, 29 Sep 2003 10:28:58 PDT)
Dear All,
On the second day of the IBSA Symposium Leighan Mossop, an employee at the
Cape Peninsula National Park, talked about the plant trade and their
efforts in the park to protect the biodiversity of their flora. The three
problems are development, alien vegetation, and illegal collection of
plants by rare plant collectors and medicinal plant collectors. She told us
that about 3000 plants had been used for medicine and some of them for
thousands of years. So there is a demand for these plants. Syndicates have
been developed to supply medicinal plants to areas that don't have them.
The next talk was given by Ernst van Jaarsveld who is the curator of the
succulent collection at Kirstenbosch. His talk was entitled, "Cliff Hanging
Bulbs." He told of going out to search for these plants and showed pictures
of some of his adventures and some of the ones he had found. Many have
rounded or compact leaves and some are very tiny. If you can obtain them
they often are easy to grow and make good basket plants. Some of them
retain their drooping nature in cultivation. Sometimes bulblets drop down
and you can find them if you look for them on the bottom of the cliff. Seed
is dispersed by wind or gravity.
Rachel Saunders presented a paper of Charles Craib's on Zantedeschias from
Sekhukuneland. She showed pictures of some yellow flowered species, Z.
jucunda, Z. pentlandii, and another one which may be a new species. The
latter grows in an area that is very wet in summer and dry and sunny in
winter and blooms all summer if the soil remains wet. It smells like a
Tulbaghia.
The next speaker was Jim Holmes who has a very large nursery in
Stellenbosch that sells bulbs. He also exports. Many of us enjoyed visiting
his nursery after the Symposium. Jim's talk was on Oxalis. I found the talk
very interesting and took a lot of notes especially about different species
and their habitats. This information is often difficult to come by and
unfortunately this genus was not included in the new Manning and Goldblatt
Encyclopedia which has given us so much good information about other
things. Right before this talk in a conversation during the tea break I was
told by one of the advisors on the book that Oxalis was not included
because it was not a bulb. I asked what it was then and thought it was
certainly a geophyte and corms, rhizomes, and tubers were included in the
book. I couldn't get an answer. Jim told us of a woman who was working on
the Dna and the biology of this genus. He told us she had determined that
the South African Oxalis were true bulbs. In the book Cape Plants 118 are
listed in the Cape Floral Kingdom so that may be the reason they are not
included in the Encyclopedia. That section would have been very long and
the key a huge challenge. Jim said Oxalis was the largest South African
genera of true bulbs. There are 206 species and 270 varieties and probably
a 60 or 80 species waiting to be described. He said there were 45 forms of
Oxalis flava alone. We have talked on this list about how it is rare for
most of the Oxalis in cultivation in countries besides South Africa to set
very much seed. This contrasts with South Africa where a lot of seed is
produced that is projected from the plant and almost immediately starts to
germinate making it impossible to save for seed exchanges. If you grow a
number of different species and are not careful you will soon have mixed
species in your collection. We saw good examples of this in the Karoo
Botanical Garden in Worcester where in some of the pots there looked like
there could be three or four different things. I can't imagine how they
could ever be sorted out. Why the difference I wondered. Lack of
pollinators perhaps? Jim said Oxalis has a very short dormancy and
delegates from Australia observed the same thing. I found that very
interesting because in California with our dry summers the dormancy for my
Oxalis is just as long as it is for many of my other South African bulbs.
Some of mine start going dormant in late spring and there are no signs of
action until mid fall in some of them even if I water them. Apparently just
a little moisture can be enough to start them into growth and perhaps we
don't get enough. Even when I water dry pots the water often runs down the
side of the pots and doesn't really get the soil moist right away. I know
there are a number of people on this list very interested in Oxalis so I
hope if I haven't reported any of this accurately that Jim will correct me.
The next speaker was scheduled to be Harold Koopowitz speaking on Clivias
in California, but he was unable to attend. We had all been intrigued with
all the wonderful plants that IBSA members brought and placed on display
tables under lights (it was cold and raining remember) hoping they would
open. So Harold's time was spent talking about some of these plants that we
all clustered around during the breaks with a cup of something hot in our
hands.
After lunch we were treated to a Floral Rhapsody, a double projector slide
show with music of some of the wonderful South African flowers arranged by
Alan Horstmann and guaranteed to keep us awake. The pictures from several
different photographers were first rate and we felt like even if we weren't
going to see the floral displays we had read about in the field we could at
least see them on screen.
The next speaker, Robin Jangle gave a most interesting talk on Gethyllis.
It's another talk that I took a lot of notes on and would be worthy of an
entire email. There were a lot of Gethyllis in leaf on the display tables.
I found them absolutely fascinating even without flowers or the fruit which
appears at an entirely different time as the leaves or the flowers.
The final speaker was Dave Lehmiller from Texas talking on Crinum. A lot of
IBSA members are more interested in growing species than hybrids. Dave
showed a lot of species of Crinum that he has seen in the wild and then
showed the results of hybridizing between the different species. The
results produced plants that were often different and he thought improved.
His talk generated a lot of interest I suspect in people that hadn't
expected they would find a talk about hybrids so interesting.
Tomorrow I will write about the field days.
Mary Sue