The Brandvlei Dam lies between the towns of Worcester and Rawsonville in the Western Cape. It is surrounded by

a vegetation type identified as Breede Shale Renosterveld which, typical of all fynbos vegetation types, evolved with fire. This means that it needs periodic burning to restore the veld and ensure the survival of several plant species that are sensitive to competition. The remaining natural areas around the Brandvlei Dam are surrounded by farming communities with associated powerlines, roads, buildings and croplands. Because natural fires (started by lightning) and fires caused by humans are extinguished as soon as possible due to their threat to the various farming activities, the renosterveld vegetation on the northern edge of the dam had not burned for over 70 years.

The Applied Behaviour Ecology and Ecosystem Research Unit (ABEERU) of the University of South Africa has been conducting a long-term vegetation study and monitoring project on the hills and footslope areas surrounding the Brandvlei Dam. Preliminary results raised concerns that renosterbos domination, as a result of the absence of fire and grazing, noticeably on the moist southern slopes, was impairing the reproduction and survi val success of some

plant species, especially geophytes (plants with underground storage parts, like bulbs) and other species sensitive to dense canopy cover and competition.

Some areas around the dam are used for fishing and recreational purposes, and people making fires there posed a threat to the surrounding area as no proper firebreaks had been maintained to cope in the event of a runaway fire.

The processAs part of the larger ecological research project it was decided to initiate a controlled burn in a section of the area to investigate the effect of fire as a management tool for the ecosystem, and simultaneously to assist in protecting the area. As the study area lies on the border of the Fynbos and Succulent Karoo Biomes, concerns about the re-establishment of the vegetation after fire were raised, and Tony Rebelo was approached for advice. His expertise was an invaluable contribution to the project.

Already at the end of the summer of 2009, time was running out for a fire. We were trying to simulate natural conditions, which meant that we needed a fire to happen before the start of the rains and the subsequent

growing season in autumn. In collaboration with Erwin Weidemann of the Department of Water Affairs (DWAF), Hannes Botha and Charl du Plessis, both from the Department of Agriculture, the area to be burned was investigated. Valuable advice was also given by Odette Curtis, from the Renosterveld Project, who has much experience in burning renosterveld. It was decided to burn an area of approximately 15 ha and, after approval of the fire plan by the Breede River District Municipality’s Fire Department, a fire permit was issued. The deputy head of the Fire Protection Unit, Hermie Visser, offered to assist on the day of the burn.

Because several rare and endangered plants grow in the study area, the report was also sent to Garth Mortimer, CapeNature, Rawsonville, and Deon Rossouw, Conservation Manager of the Limietberg Nature Reserve, who offered valuable advice and support and used the burn as a training exercise involving some of the Limietberg Nature Reserve’s personnel on the day of the burn.

As three powerlines run through the area, the proposed site for the burn had to be inspected by area managers of ESKOM ( Transmission and Distribution divisions). Thick smoke caused by fire under

ABOVE: Fire-fighters along the firebreak, guarding the back-burn. LEFT: The head-fire is checked here by the Strike Force team of the Fire Brigade. BELOW: Employees of DWAF cutting a firebreak in old renosterveld. Photos: Anso le Roux.

Brandvlei burnsA controlled burn in Breede Shale Renosterveld gives new life to plants, including the hitherto unknown Moraea vuvuzela by Anso le Roux, ABEERU, UNISA

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powerlines can act as a conductor which could cause the lines to earth, thereby endangering the lives of everyone in the immediate area. Both reactors at the Koeberg nuclear plant were down at the time, so ESKOM allowed no fires within 5 km of their transmission lines as these were some of the few lines supplying the Cape Metropolis with electricity.

In preparation, workers from DWAF, as well as private neighbouring landowners, cut three firebreaks to protect an erosion site and various human structures. When DWAF were satisfied with the firebreaks, the fire was formally permitted after a site inspection.

After taking the weather forecast into account, the provisional date for the con-trolled burn was set for Wednesday 8 April 2009 – if the reactor at Koeberg was operating. Fire protection trailers were organized from DWAF, the Goudini Landbouvereniging and also from the Goudini Spa. The day before the burn a line of irrigation pipes was assembled at the foot of the steep slope in the firebreak in order to water the firebreak as much as possible to improve safety conditions as the area was very steep and difficult to reach by vehicle. Workers spent the night at the site,

keeping the pumps running and the sprayers moving along the 20 m firebreak from which the back-fire would be started. It was crucial that the fire could not jump this break, as a fire in the dense, overgrown renosterveld on the other side would be impossible to control. Thankfully, we got the go-ahead from ESKOM after a final inspection.

The day of the burn was wind free. A briefing was given by Hermie Visser and Deon Rossouw who co-ordinated proceedings. In total, 96  people were present. The vehicles carrying water and fire-fighters were positioned along the 20 m break. When everything was in place, the fire was started by Erwin Weidemann and carried further by two employees from the Limietberg Nature Reserve lighting a line of fire with drip torches, firstly in an easterly direction from the main firebreak, and later in a northerly direction along the road firebreak. The intention was to light a head-fire in the slight south-easterly wind when the back-burns were appropriately secured to the west.

Some mist set in around daybreak, and it was difficult to get any fire going, let alone an even line. An early start had been recommended because of the inflammable oils and contents of the vegetation and everybody was surprised

at the difficulty getting the fire going. With the Breede River directly to the north and the Brandvlei Dam to the south, early morning conditions were just too moist to sustain a fire. But conditions improved later and by midday, though still patchy, the fire was burning well. Controlled burning regulations state that burning must be done in temperatures lower than 28 °C, a relative humidity of more than 25% and wind speed of maximum 10 km/h. To do this, and to simulate natural conditions, a hot fire is needed. It was clear that weather conditions within the regulations could defin-itely not sustain a hot fire on an early autumn morning here!

In order to safeguard the site prior to exp-ected windy conditions later in the afternoon and evening, the lighting of fires was stopped at 14h00. A south-westerly breeze, which completely changed direction to north-east, resulted in burning most of the unburnt patches in the planned area before the fire was put out by the fire-fighters at round about 18h00. It was a long day.

The team of Working on Fire (WOF) spent the night and the next day ‘mopping up’ – smothering remaining smouldering embers and securing flare-ups.

LEFT: The dedicated fire-fighters of the Working on Fire team continuously checked the site. BELOW LEFT: Only a week after the fire, a Powder-puff Lily (Haemanthus coccineus) came up between the charred branches of a Botterboom (Tylecodon paniculatus). BELOW CENTRE: Carpets of seeds from re-seeders such as Protea laurifolia covered the ground. BELOW: The first flowers of Gladiolus guthriei appeared two months after the fire. Photos: Anso le Roux.

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The outcome Thanks to thorough planning and the dedicated contribution of everybody invol-ved, the project was completed successfully. Admiration, appreciation and much gratitude is owed to everyone.

In a natural scenario, fires started by lightning, mostly during late summer, in the surrounding mountains could be carried further by prevailing south-easterly and north-westerly winds. This could result in fires on the floodplains and in the renosterveld on the foothills of the mountains. In this project, care was taken not to burn when the geophytes were emerging after the dry season. The decision to burn when we did turned out to be perfect timing indeed as lightning did start a fire three days before the controlled burn was done.

Monitoring The long-term research project involves continuous monitoring of the burnt reno-sterveld, which assesses the re-seeding, re- sprouting and overall response of the vegetation to the fire.

In the first growing season after the burn, the area was monitored every second week.

We walked through the veld, noting the occurrence of sprouting bulbs, re-growth, seedlings and any other relevant data. Fixed point photographs of the different slopes were taken as well.

After the first growing season following the burn, the area will be monitored monthly.

What we have learnedBurning the old veld proved beneficial for most species. Members of the Proteaceae (protea family) shed their seeds and geophytes flowered prolifically in the spring of 2009 especially Gladiolus guthriei, G. recurvus, G. hyalinus, Watsonia spectabilis, Disa satyrioides and other orchids. Species of Asteraceae (daisy family) such as Arctotis, Berkheya, Othonna and especially Pteronia hirsuta grew vigorously and flowered pro-lifically. All genera of the Iridaceae (iris family) benefited from the burn, especially Tritoniopsis ramosa and the recently dis-coverd Moraea vuvuzela* which were not seen in such vast numbers before the fire. Before the burn the latter, a small moraea, was only occasionally seen and had not been formally collected. Only after the burn were large stands of them seen on the south facing

slopes of the study area permitting formal collection and consequent description. (See the cover photo of this issue.)

Evidence of post-fire succession was the healthy grass layer that covered the moister southern slopes in December 2009.

The fire has benefited various smaller plant species and numerous geophytes, thought not to be present, appeared and flowered within a few weeks of the fire. Even though the research project is continuing with various monitoring plots placed in the burnt and un-burnt areas, the preliminary results indicate that although the vegetation structure has changed, with numerous other species appearing, the dominant species still persist.

* A new species, noticed by the author, Anso le Roux, and described by Peter Goldblatt and John Manning, was named in honour of South Africa’s successful hosting of the 2010 Soccer World Cup which, for most of the world, will be memorable because of the vuvuzela. Anso le Roux first saw the ‘new’ moraea five years ago during fieldwork for her UNISA ecological studies, but only encountered a few solitary plants with not many of them flowering. After the burn, the moraea plants flowered so prolifically they were called a common weed by visitors to the site. She then collected specimens for the herbarium, and alerted plant taxonomist John Manning to them. John Manning then came out to see them in habitat, and the rest of the vuvuzela story is history (see further reading list below).

READINGBooysen, P. de V. & Tainton, N.M. 1984. Ecological effects of fire in South African ecosystems. Spriger-Verlag, Germany.Goldblatt, P. & Manning, J. C. 2010. Moraea vuvuzela and M. intermedia (Iridaceae-Iridoideae), two new species from western South Africa, and some nomenclatural changes and range extensions in the genus. Bothalia 40 (2), 147-154.Mucina, L. & Rutherford, M.C. (eds). 2006. The vegetation of South Africa, Lesotho and Swaziland. Strelitzia, 19.

ABOVE: Pteronia hirsuta grew and flowered extraordinarily prolifically after the fire. ABOVE LEFT: Oxalis pardalis flowered prolifically two months later. BELOW LEFT: Moraea vuvuzela flowered abundantly after the fire. Photos: Anso le Roux.

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