The demand for wood-based fabrics, including viscose and lyocell, is growing. Broadly, there are two reasons for this – people are drawn to the qualities of these fabrics, and as their concern grows for climate change, biodiversity loss and environmental degradation they want wood-based fabrics that are responsibly and sustainably sourced and manufactured.

Explaining why she uses these fabrics, fashion designer and creative director of Guillotine, Lisa Jaffe says, “Viscose is soft, drapey and malleable. It has a luxurious handle and is beautiful to pleat.” Sustainable fashion brand Asha Eleven’s Olivia Kennaway agrees adding that she uses wood-based fabrics such as lyocell.

Verve, a division of Sappi, grows eucalyptus trees to produce the wood pulp for the production of these textiles (and other products). In fact, Sappi is the world’s largest supplier of dissolving wood pulp for the world’s largest textile fibre producers, and it provides over 50% of the pulp used for the production of lyocell.

If you didn’t know this, lyocell is a next generation wood-based fabric made with reduced chemical processing and implementing closed loop systems to reduce emissions and water usage, and to avoid polluting the environment. Lyocell is the generic word used for this wood cellulose fabric. You would have heard of Tencel which is the brand of lyocell produced by the Austrian company Lenzing. Asha Eleven likes to use Tencel as well as Ecovero, another wood-based fabric by Lenzing, which is certified with the EU Ecolabel. Olivia says, “For us, wood-based fibres allow us to produce a good, long-lasting product and ensure reduced environmental impact at the same time.”

I recently joined a group of textile experts on a tour of Sappi in KwaZulu-Natal. Sappi grows trees and produces dissolving pulp for the manufacturing of wood-based fabrics and other products. Sappi, an international company head-quarted in South Africa, is one of the biggest private landowners in the country. Operating at such an immense scale across borders, comes with huge economic, social and environmental responsibilities. Farming trees in an era of climate change and biodiversity loss requires meticulous planning and management. And, operating in a country with the highest levels of unemployment and inequality in the world comes with additional social responsibilities.

To give you an idea of Sappi’s size, the company employs 12 239 people (4591 in South Africa), has 400 000 hectares of (owned and leased) land under forest plantations in South Africa. It produces 2.3 million tons of paper pulp and 1.4 million tons of dissolving wood pulp for textiles and other uses. It’s the textiles we’re interested in – how do you make a fabric from wood?

In brief the process of making lyocell (and viscose) starts with Sappi growing trees in Forest Stewardship Council and Programme for the Endorsement of Forest Certification-certified plantations. After harvesting and logging the wood, the wood is chipped and cooked in a chemical process to make a dissolving pulp which is dried and packaged in baled sheets and rolls. These dissolving wood pulp sheets are exported and sold onto textile producers that dissolve the sheets into a liquid which is extruded through spinnerets, making thin viscose fibres that are then processed into yarn. Local demand is not big enough to make it viable to do this processing in South Africa.

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  Wood chips

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  Dissolving wood pulp

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  Fibres

For five days, we travelled from Durban to Pietermaritzburg, Howick and Tweedie, and through the Valley of a Thousand Hills to Umkomaas and back to Durban.

A focus on water

Water is key for Sappi’s production. Our first stop on the tour is a water catchment area of the uMkomazi River, upstream from Sappi’s Saiccor mill near Durban. The mill is dependent on the river for its production needs. To secure its water supply for future use, Sappi needs to take responsibility of this water source. General manager Sustainability, Krelyne Andrew says, “For the consistent production of viscose and lyocell, we need a consistent supply of water”.

Textile experts visit the uMkomazi River catchment area with Sappi

In the midday heat, we walked to a lookout point over a vast and beautiful valley where we met with Sappi partners – representatives from the communities in the area, the World Wildlife Fund South Africa and the Institute of Natural Resources. Co-ordinated effort is required to protect this water source. Not only is this essential to operations, but water scarcity would also have a devastating impact on the rural communities living along the river. Cattle grazing practices have been improved to avoid soil erosion, alien vegetation removed, land is being restored and rehabilitated, and there is a focus on wild fire prevention and fighting. “Wildfires are a major threat to forestry operations and cause greenhouse gas pollution,” says Krelyne. These environmental activities are creating jobs which Krelyne says, “Is front and centre of our engagement in the catchment area leading to sustainable communities.”

Tour group learning about the importance of the uMkomazi River to the community living along the river and its importance to Sappi operations

A few weeks after our trip, I called Dr Alistair Clulow from the University of KwaZulu Natal, who said that under South African legislation Sappi is issued a water licence (for which it pays) because its operations reduce the annual flow of water – called a stream flow reduction activity. Clulow explains that commercial forests, which are rain fed, use more water than the natural habitat would (more in summer but far less in winter), but not more than other agricultural activities.

Along with its water catchment programmes, Sappi protects the streams and wetlands in and near its forests. Environmental officer for Sappi Forests in KwaZulu-Natal Wesley Evans told us that, “Wetlands are the most threatened ecosystem in South Africa.” As a custodian of these wetlands, Sappi is not permitted to plant within 20 metres of water sources to prevent trees from drawing water from these sources.

Krelyne says, “A third of Sappi’s land holdings remains unplanted for conservation reasons”. These areas include indigenous forests, grasslands, wetlands and river systems.

Research and development

Climate change is an urgent risk and to adapt and mitigate this risk, research and development are critical to planning for the future sustainability of forestry. Climate change brings the unpredictability of drought, wildfires, pests and diseases, as well as extreme weather events. Krelyne says, “We must plan for the future to ensure viable and sustainable production.”

Following the day understanding the importance of water and environmental considerations, we visited the Sappi Shaw Research Centre in Tweedie, where tree breeding, climate change and horticultural experts research and develop better forestry practices and optimal hybrid varieties for wood pulp quality and climate change mitigation. Sappi has seven similar facilities operating around the world.

The tour group listen to research experts at the Sappi Shaw Research Centre in Tweedie

Tree breeding is considered the most important climate adaptation strategy. Wood density, moisture, growth rates and resilience are monitored on an on-going basis. Sappi uses this data to develop and improve sustainable and responsible plantation management methods.

Growing and planting

Sappi predominantly grows eucalyptus trees – the ingredient of viscose and lyocell – which are native to Australia. If not managed properly, they can lead to significant environmental issues such as reduced biodiversity and soil degradation. It’s crucial to implement sustainable forest management practices to mitigate these risks and preserve the ecological balance.

Sappi plants 60 million trees a year, which grow between nine (eucalyptus) and 20 years (pine) before harvesting. After optimal species and hybrids are bred, nurseries take care of nurturing seedlings and the rooting of cuttings before they are planted out in plantations.

Sappi plants 60 million trees a year. These trees start off as seedlings in nurseries 

Application of fertilisers and sprays – in Sappi’s case – are governed by FSC certification rules. The Biodiversity Consultancy’s Helen Temple says, “Big industry needs to weigh up use of poisons with loss of plants due to not spraying.”

Saplings are planted on land owned by Sappi and also in partnership with communal farmers, small growers and commercial farmers. Once the trees are matured, they are harvested and logged – each tree produces about four logs – and stripped of their bark in the plantations. These are then trucked by 22 and 32 metres-long trucks to mills where they are washed before the pulping process begins.

Lyocell (a type of viscose) fabrics are made using wood pulp from eucalyptus trees harvested from plantations that are Forest Stewardship Council and Programme for the Endorsement of Forest Certification-certified 

Harvesting

Sappi Forestry Manager Andrew Pool says, “Harvesting involves us ensuring that wood meets the quality and FSC requirements. For instance, from a quality perspective there should be no mud and no burn damage on the logs.”

Eucalyptus trees mature after eight years after which they are harvested and logged. Each tree produces about four logs

While burning of agricultural waste is generally discouraged for environmental reasons, the debris left after Sappi’s tree harvesting is control-burned to prevent the much more devastating effect of wildfires.

When the logs reach the Saiccor dissolving pulp mill they are chipped first before they can be pulped

The process of planting, harvesting and trucking is tracked throughout so that the textile producers and the final customer can be assured of a transparent chain of custody.

From wood to dissolving pulp

Sappi manufactures dissolving pulp in two mills in South Africa (Saiccor near Durban and Ngodwana Mill near Mbombela) and one in North America. A visit to the Saiccor dissolving pulp mill near Durban requires wearing protective gear, hearing protection and walking up five floors of step ladders to get a bird’s eye-view of the huge site.

The Saiccor dissolving pulp mill near Durban

Once the logs are delivered to the mill, they are chipped into small bits by three large chippers. Then depending on the type of eucalyptus tree they are sent to one of three types of cookers: a slow, medium or fast cooker, in which they are dissolved by cooking. The dissolved wood pulp is then compressed into sheets.

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  Inside the mill

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  Filters, like this one, are part of the bleaching and washing process

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  Bleached pulp

This industrial process at this mill is not 100% circular: not all energy is renewable and greenhouse gasses are emitted. But these emissions have been reduced by 25% from 2019, with efforts to further reduce these emissions, while the use of renewable energy continues to grow. For instance, waste sawdust is turned into biomass for energy.

The dissolved wood pulp is compressed into thick sheets which is exported to international textile producers, such as Lenzing in Austria and Birla Cellulose in India where forest-friendly fabrics such as lyocell are manufactured

From the mill, the cellulose pulp sheets are sent to textile producers that turn them into viscose or lyocell fibre by dissolving the sheets of wood pulp into a liquid which is extruded through spinnerets (a device through which a substance flows to create fibres), leaving thin viscose fibres that are then processed into yarn.

Conclusion

The process of making viscose or lyocell starts with communities looking after water and the biodiversity of our natural environments. It involves scientists and botanists researching best practices. It involves thousands of people across nations – South Africa, Austria, India – to produce a fabric. Scarce natural resources are used in the process. This effort is huge and comes with responsibilities.

The next time you wear your viscose or lyocell shirt or dress, consider the long and careful process it took to get that fabric onto your body. Take good care of it.

 

• Additional reporting by Nabeela Karim
• Photography Jackie May, Madelaine Fourie and Nabeela Karim
• Jackie was invited by Sappi to attend a learning journey in March 2024