As some of you may know, I have recently joint the Overberg
Lowland Conservation Trust as a freelance consultant to help Odette with a wide
range of jobs and duties. My first task was getting to grips with what the
Trust does and of course what Renosterveld is. Fynbos and Renosterveld have intrigued
me ever since I moved to South Africa. However, the sheer diversity of these vegetation
types with their huge numbers of endemic species baffles a Western European trained
environmental scientist at the same time.
As you can imagine, my learning curve has been a rather
steep one, so thought I would share some Renosterveld facts that amazed me
most.
Did you know?
Fynbos is the generic
name for all 119 vegetation types in the Cape Floristic Region.
True Fynbos is generally associated
with poor acidic sandy soils found in more mountainous and coastal regions and is
characterised by a dominance of proteas, ericas (heather), and restios (reeds).
Renosterveld is generally found
in lower lying areas on more fertile, clay- and shale-based soils, and is typified
by the absence of these three ‘Fynbos indicators’. Instead it is dominated by Asteraceous
shrubs, i.e. shrubs belonging to the daisy family of which the Renosterbos is one example, and often a
diversity of grasses.
Renosterveld is not only the richest bulb kingdom in the world and it
also has extremely high species diversity with literally 100s of different plants
found in just a few hectares of Renosterveld.
New Renosterveld species are
discovered all the time, like the Hesperantha kiaratayloriae, a little Iris that grows
only on quartz patches in the Eastern Rûens and till now only a single
population of this rare plant has been recorded.
Renosterveld originally covered the entire lowlands of the
Overberg and only an estimated 4-6%
remains today.
There are four types of Renosterveld found in the Overberg, Central
Rûens Shale, Eastern Rûens Shale, Western Rûens Shale, and Rûens Silcrete
Renosterveld. All are Critically
Endangered.
We don’t really know what original Renosterveld looked like, as these veld types were
radically transformed through livestock grazing and subsequent ploughing
relatively soon after European settlement.
We believe that Fynbos was once grazed by large mammals, like black rhino, eland, red
hartebeest, bontebok, quagga, and blue buck. Some of these are sadly now
extinct.
Renosterveld is highly fragmented with over 12,000 remnants left. This may sound a
lot, but 99% of those remnants are smaller than 80 ha and some are as small as
0.0001 ha.
The high occurrence of endemic and rare
species makes Renosterveld extremely vulnerable to fragmentation, which often leads
to high risks of extinction.