Corking carbon emissions


Spekboom, or Portulacaria afra – a humble
plant with the potential to make an
immense environmental impact.
(Image: Wikimedia)

Eventually the once-lush spekboom
thickets will be restored.
(Image: Wikimedia)

The first spekboom nursery has been
established at Lelienfontein, vine supplier
to the industry. (Image: Lelienfontein)

Janine Erasmus

South African-based food packaging and processing company Columbit has launched an initiative to encourage its wine clients to reduce their carbon footprint. The company is distributing specimens of the indigenous spekboom plant, known for its immense carbon-absorbing properties, for their tasting rooms as a reminder of the need to keep carbon emissions down.

Columbit has set up a spekboom (Afrikaans, meaning “pork bush”) nursery at Lelienfontein, Africa’s largest vine nursery, located in the viticultural region of Wellington, Western Cape. Propagation of the so-called superplant is overseen by R3G, the Rhodes (University) Research Restoration Group.

R3G comprises a group of environmental scientists who monitor and evaluate environmental restoration projects and then develop best practice protocols to address and counter the damage. One of these is the replanting of spekboom (Portulacaria afra) cuttings in degraded thicket sites.

Columbit will issue potted spekboom plants free of charge to wineries and producers who purchase its bottle corks, thereby creating awareness of the environmental capabilities of the plant as well as the importance of reducing carbon emissions.

The company has approached the Department of Water Affairs and Forestry, under its Working for Water programme, for funding to plant more trees. The long-term benefits will be greater carbon absorption and the creation of jobs in caring for the trees and associated agricultural activities.

The initiative has already begun, with the first spekboom plant taking root at Schalk Burger & Sons’ winery in Wellington.

Good corporate citizenship

The project is Columbit’s first in terms of its membership of the United Nations’ Global Compact for good corporate citizenship. The company, which joined the global initiative in December 2008, was the first member from the wine industry to do so. To date there are over 6 200 signatories to the pact, from over 130 countries.

The Global Compact is a strategic policy initiative for businesses that have committed to aligning their operations and strategies with 10 universally accepted principles in the areas of human rights, labour, environment and anti-corruption.

The 10 principles encourage businesses around the world to work towards common beneficial goals such as the elimination of all forms of forced and compulsory labour and child labour; the fight against corruption in all its forms; the protection of human rights; and the promotion of greater environmental responsibility.

Columbit has not only pledged to support the 10 principles and make them part of its day-to-day, cultural and strategic operations, but also to advance those principles within its sphere of influence.

“This compact is of great significance internationally,” commented Columbit CEO Tony Haughton, “and our joining is therefore an important occasion for us and the industry.”

Putting a cork in it

According to Columbit’s marketing manager Bridget Davidtsz, to calculate the carbon emission of a wine one must take into account every step of the manufacturing process, from start to finish. This includes emissions from nitrogenous fertilisers, carbon absorption by vines, fuel use, refrigeration, fermentation emissions, carbon dioxide used during processing, waste treatment, packaging, freight and employee travel.

“Our wines travel vast distances to reach their outbound destinations,” she explained. “As a result the carbon footprint attached to our wine production is automatically higher than some of the nations we compete against.”

Davidtz encouraged all wine producers to embrace the spekboom project and to use cork as their closure of choice, as it is renewable, recyclable and biodegradable. Furthermore, cork is obtained through one of the world’s most environmentally friendly harvesting processes.

“It made sense that we use the sale of cork as the basis for the spekboom project,” she added. “With the support of the industry, and in partnership with R3G, we hope to see a drastic reduction in the carbon footprint of wine.”


Spekboom is a leafy succulent found prevalently in the Succulent Thicket biome that occurs on steep mountain slopes in the Eastern Cape province and the eastern parts of the Western Cape.

R3G studies conducted on the extraordinary plant over the past seven years show that it is capable of storing more than four tons of carbon per hectare per year – as much as some subtropical rainforests.

Distinguished botanist Professor Richard Cowling of the Nelson Mandela Metropolitan University, and Dr Anthony Mills of Stellenbosch University’s Soil Science department, published a report in 2006 on their research conducted on spekboom thicket in the Baviaanskloof Nature Reserve, the Addo Elephant National Park and the Great Fish River Reserve.

This led to the establishment of the Baviaanskloof Subtropical Thicket Restoration Project, a Department of Water Affairs and Forestry project that aims to rehabilitate the degraded thicket biome. From the 1930s and onwards at least 800 000ha of once-lush thicket land, especially spekboom, has been severely over-exploited and over-grazed, mainly by goats.

To monitor carbon absorption, the scientists turned to an area of restored spekboom, planted 27 years ago to cover degraded hillsides, on a farm near Uitenhage in the Eastern Cape.

According to Cowling, growth of the two-metre high plantation was “almost miraculous”, despite a meagre rainfall quotient of only 250-350mm per year. Each hectare of spekboom on the farm sequestered an annual 4.2 tons of carbon, the equivalent of over 20kg per square metre of vegetation. Carbon sequestration is the term describing a variety of processes that remove carbon from the atmosphere.

Cowling and other scientists working on spekboom restoration projects are very interested in the implications for South Africa in the international carbon trading market. The carbon trading system allows heavily polluting businesses to buy carbon credits, while environmentally efficient businesses can sell surplus credits at a profit. The system is a component of the Kyoto Protocol.

“The vision is to tap into the international carbon market and thereby restore hundreds of thousands of hectares of degraded thicket,” said Cowling, “provide tens of thousands of jobs in the process and create a source of income for rural communities for many decades.”

Thicket replanting requires intensive labour, and carbon monitoring offers opportunities for skills development. Goat farming under managed conditions is also feasible, as goats are partial to spekboom.

Farming for carbon credits

Anthony Mills of Stellenbosch University has carried out an extensive study into the possibility of farming to generate carbon credits and has developed a system for farmers.

“The price of a carbon credit is between R130 and R260 ($12.9 and $25.7 respectively) per ton of carbon dioxide,” he said. “This is expected to exceed R778 ($77.1) by 2030. The bottom line is that the carbon market is booming and creating carbon credits is likely to be profitable.” Presently, the market in Europe is worth R100- to R200-billion ($9.9- to R19.8-billion) a year.

In order to qualify for trading on the international carbon exchanges, the system has to be certified under the Clean Development Mechanism of the Kyoto Protocol. This is an arrangement whereby emission-reduction projects in developing countries can earn certified emission reduction credits. Each credit is equivalent to one ton of carbon dioxide. Credits can be traded and sold, and used by heavily industrialised countries to attain compliance with their emission reduction targets under the Kyoto Protocol.

If this cannot be achieved the alternative is to sell credits through a reputable voluntary market system.

Mills says the potential income from goat farming could be as much as R200 ($19.8) per hectare per year, while annual potential income from carbon credits, once production is in full swing, could soar above R1 000 ($99.1) per hectare.

A December 2008 report in Engineering News revealed that spekboom planting is one of the mechanisms under consideration by South African fuel giant Sasol, to offset carbon emissions at its new-generation coal-to-liquids plant in Limpopo. The plant, dubbed Project Mafutha, is currently in the prefeasibility stage but initial studies suggest that Mafutha’s entire carbon footprint could be offset by planting 100 000ha of spekboom.

In addition to its carbon-mopping potential, spekboom is also used as a soil binder for preventing soil erosion. Known as Elephant’s Food, spekboom is an important component of the diet of elephants in the Addo Elephant National Park, and visitors can often see the huge beasts chomping on abundant stands of the pink-flowered plant.

Spekboom leaves are edible by humans and are said to have a sour or tart flavour. This plant is also eaten by domestic livestock such as goats, as well as game, and is a particular favourite of tortoises.

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