Preserving harakeke taonga
Māori have many traditional uses for harakeke (Phormium tenax) such as the making of traps and fishing nets and the weaving of whāriki (mats) and kete (baskets). Harakeke is also important for the production of textiles, for example, muka, a prepared flax fibre, is frequently used as the base for kākahu (clothing) or korowai (cloaks).
The problem with harakeke
Rangi Te Kanawa, a textile conservator at The Museum of New Zealand Te Papa Tongarewa, faces the problem of rapid deterioration in dyed harakeke artefacts such as garments and mats. In order to ensure these precious taonga survive, she worked with Dr Gerald Smith from the School of Chemical and Physical Sciences at Victoria University and Landcare Research staff to analyse and to develop an innovative new conservation method.
Point of interest
In this clip, Rangi Te Kanawa and John Campbell talk about the breakdown of harakeke. They explain that harakeke has high hemicellulose content, and this compound produces acetic acid when it breaks down. Acetic acid further accelerates the breakdown of the harakeke artefact that produced it, and being prone to vaporise, it can float off and affect other exhibits or stored items. In the museum environment, this is referred to as ‘vinegar syndrome’.
Rangi Te Kanawa (Ngāti Maniapoto), a textile conservator at The Museum of New Zealand Te Papa Tongarewa, faced the problem of rapid deterioration in the harakeke kākahu. Of particular concern was the rapid deterioration of the fibres that had been dyed black using a traditional method where the fibre is immersed in paru (mud).
Te Papa has the largest collection of Māori textiles in the world. Amongst these important taonga are 400 kākahu, and most utilise a muka backing with feathers, dog skin and other decorations woven into the front of the kākahu.
For Māori today, these textile taonga are not only a living connection to their ancestors, they’re also a rich repository of knowledge about crafting and weaving techniques.
Te whāinga – the goal
Rangi needed to find a way to prevent the deterioration in order to protect these precious taonga tuku iho and their valuable intellectual property for future generations.
Damaged piupiu
This piupiu, a precious family taonga, was showing significant damage from time. Sections of black fibre that make up the patterns in the piupiu are broken, and some of the pokinikini that hang from the waistband have fallen off.
Rangi teamed up with Dr Gerald Smith, Associate Professor of Chemistry at Victoria University. Gerald specialises in the chemical and physical processes responsible for the degradation of organic materials and teaches a course in heritage material science.
Rangi, who comes from a long line of weavers, brought specialised mātauranga (knowledge) accumulated over generations within her whānau. Rangi and Gerald used their combined knowledge to identify what was responsible for the deterioration of the textiles and how they might work to counteract it.
When I began my training as a conservator, I realised then that there was a problem – a problem that I’d been witness to as a child, watching mum and nana put this fibre muka into mud.
Rangi Te Kanawa, textile conservator, Te Papa
Rangi and Gerald’s work was able to identify the chemical reactions causing the damage – the breakdown of acetic acid produced by the harakeke that, when released, further accelerated the disintegration of the textile. The black dyed fibre was significantly more vulnerable because the dying process introduces tannins in the paru.
Solution
Having determined the key cause of the damage to the textiles, Rangi and Gerald began to research a possible solution to either neutralise or reduce the acetic acid.
Rangi Te Kanawa with korowai
Textile conservator Rangi Te Kanawa (Ngāti Maniapoto) with a damaged korowai from Te Papa Tongarewa collection.
Rangi came up with a novel solution using alginate from seaweed. Gerald was able to test this by accelerating the deterioration of fibres in an oven. The fibres that were pre-treated with the solution – and those that weren’t - were then tested using a gas chromatograph. This showed that the alginate solution neutralised the acetic acid.
Gas chromatograph
An important tool in Gerald’s lab is the gas chromatograph.
Atmospheric chemist Dr Katja Riedel also uses a gas chromatograph. In the above video she explains how it works.
Measuring gas concentrations
Dr Katja Riedel of NIWA explains that the air collected from the ice cores contains a mixture of different gases, and she describes which techniques are used to separate and measure them.
Rangi is now using the innovative alginate solution in her work conserving the kākahu at Te Papa.
Other indigenous cultures also use chemically-identical dying methods, and the solution is now being used by conservators around the world.
A kaupapa Māori approach to harakeke research
Dr Bronwyn Lowe at Otago University worked with Māori weavers to investigate a collection of harakeke plants at the Dunedin Botanic Garden.
Because of the cultural significance of harakeke, the research on the collection was done using a kaupapa Māori approach. This meant that the involvement of Māori weavers Kahutoi Te Kanawa, Roka Ngarimu-Cameron, Anna Gorham and Christine Holtham was paramount. The weavers chose which harakeke plants would be studied in detail and assessed the weaving properties of each one. The weavers also worked with their people to make decisions about how the results would be disseminated. Read more about this research in this article, Harakeke under the microscope.
Microscopy meets mātauranga Māori
Dr Bronwyn Lowe (University of Otago) worked with Māori weavers to explore the properties of different harakeke varieties. In this clip, Bronwyn explains how the weavers’ traditional knowledge (mātauranga) and her own findings from microscopy of harakeke leaves often echoed each other.
Rongoā
Harakeke has many medicinal uses that have been passed down to modern Māori from their tāpuna (ancestors). Read more about rongoā and medicinal native plants, in this article, Rongoā Māori.
High school student Chris Ryan researched the medicinal properties of kawakawa, read about it in this Connected journal article.
Using rongoā Māori is an activity for students learn about rongoā Māori through a silent card game.
Explore our collection of Rongoā Māori resources on the Science Learning Hub with helpful notes for teachers. Login to make this collection part of your private collection – just click on the copy icon. You can then add additional content, notes and make other changes.
Harakeke (flax)
Harakeke (flax) can be used as rongoā to fight infection. It can be used as a treatment for boils and wounds. A poultice of the root can be used to treat intestinal parasites.
Nature of science
Using science to understand problems and find solutions often leads to innovative discoveries and technologies. Combining knowledge of historic practices with new scientific understanding gives us insights into why these historic practices worked and how to use and enhance them today.
Related content
Black is back is an Connected journal article featuring Dr Rangi Te Kanawa, and has supporting teacher resources, from the Ministry of Education’s Connected series.
Useful links
Te Papa’s kākahu researchers – Learn more about Dr Rangi Te Kanawa and her fellow kākahu researchers Hokimate Harwood and Dr Patricia Wallace at Te Papa.
Listen to this Radio NZ programme Dr Rangi Te Kanawa: working to conserve our taonga kakahu from May 2022.
Watch this Te Papa video on YouTube of Rangi talking about her work and how her upbringing influenced her work in conserving the Māori cloaks in Te Papa's collection.
In the video, ethnobotanist Sue Scheele and kaitiaki Katarina Tawiri show some of the flaxes and their different properties. Harakeke samples for this research came from a collection of traditional weaving varieties of harakeke at Manaaki Whenua – Landcare Research. Explore the different harakeke in the National New Zealand Flax Collection and learn more about them.
Project Mātauranga
Watch Series 2/Episode 1: The Problem with Harakeke
Project Mātauranga is a television series that investigates Māori world views and methodologies within the scientific community and looks at their practical application. Each of the 13 episodes in series 2 shows how western science and Māori knowledge systems are combining to provide solutions to a variety of challenges.
The Science Learning Hub thanks Scottie Productions for allowing us to host these videos.
Scottie Productions
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