PopularMechanics082017

(Joyce) #1

AUGUST 2017 _ http://www.popularmechanics.co.za 17


hectares of property – the farm is
3 000 hectares – which was mostly in nat-
ural areas. Because a lot of the invasive
species we have on the property come from
Australia, they are also well fire-adapted,”
says Van Rensburg
That fire adaption and intense burning
means that the indigenous vegetation gets
destroyed in the inferno and the seeds of
the alien trees survive. Case in point is a
pine tree. If the cone explodes because of
the heat, it spreads the seeds into other
natural areas and that plant out-competes
the indigenous shrubs. “We found that
annually the distribution of invasives
increases by between 5 and 8 per cent,
which means you lose indigenous plants
by that percentage each year,” he contin-
ues. The other problem is that the intense
heat causes soil problems because the heat
penetrates a lot deeper, which further neg-
atively impacts indigenous seed cover.


A large fire in 2009 ravaged around 2 000
hectares of the farm, engulfing much of
the 1 700 hectares of land cleared up to
that point. It also consumed some uncleared
stands, but didn’t cause any significant
agricultural damage. The fire did, however,
spawn a regeneration of invasives. This
forced Vergelegen to start a project devot-
ed to reclaiming that land, alongside the
clearing project. To give some perspective
on the destructive power of invasives, Van
Rensburg explains that the massive fires
in January 2017 covered roughly the same
area as the 2009 blaze, which raged for
two months, #CapeFires lasted a mere
four days. Thankfully this year’s fires tore
through a significant portion of the 200 or
so remaining hectares earmarked for clear-
ance, of which six have been cleared since
the teams got back to work.
Fynbos fires generally occur once a dec-
ade. In fact, the Cape Nature rule of thumb

Many species of Boland Granite fynbos,
thought to be extinct, are flourishing on the
farm and recovering well after the fires. Van
Rensburg and his team are going to cross-
reference findings with records from the
estate’s historic library.

is that a blaze is due after about three pro-
tea-flowering seasons (proteas flower after
five years of growth). If the veld doesn’t
burn it can become sterile, but too-frequent
fires aren’t good either. A major fire within
eight years isn’t terrible, but the farm now
faces erosion problems such as roads wash-
ing away and dams that are silted up. The
fires did assist the initiative by incinerat-
ing a lot of the excess biomass situated in
inaccessible areas. Vergelegen had actually
planned to do the Cape’s first aerial ignition
controlled burn, but Mother Nature (or
was it Human Nature?) stepped in with
the help of a few suspected arsonists.
Another unexpected side-effect of the
clearing project has been the rejuvenation
of some streams that usually ran dry in
summer that now run all year round. the
farm is lucky enough to be in a catchment
area. Two of the three dams on the prop-
erty are at 100 per cent, with the third at
60 per cent. The farm is entirely self-suffi-
cient for irrigation purposes. Unfortunately,
the water isn’t potable.
This mass clearance of alien vegetation
has also had other effects. Because the
fires are less destructive, there is a greater
opportunity for the associated fauna to
settle. A healthy bontebok herd roams
freely across the estate and 145 recorded
bird species fly overhead. The antelope are
also ranging further up the mountain
slopes than expected, which puts them at
risk of attack from the Cape leopard popu-
lation in the Cape Leopard Trust Boland
Project study area that extends into the
farm. Of the more than 280 fynbos species
documented on the farm, 22 of them are
on International Union for the Conservation
of Nature (IUCN) Red List, a peer-reviewed
account of the planet’s most threatened
plant and animal species.
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