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ScienceJuly 25, 2017

Fighting kauri dieback with the ‘super science’ of cow dung? Stinks of bullshit


Artist Sarah Smuts-Kennedy told Kim Hill on Saturday that she has been repeating a ritual used by Peruvian banana farmers in the 1980s to treat diseased kauri. Yes, we need more research, but leave the comment to the scientists, writes Cate Macinnis-Ng.

Art can be a powerful tool for connecting and mobilising communities around scientific problems. Art can give the public a voice and provides a medium of communication between specialists and non-specialists. Art allows expression and enhances education. Art can foster reciprocal and respectful relationships between scientists, iwi and communities. But just as we wouldn’t expect a scientist engaged in such a project to start calling themselves an artist, an artist working on a scientific project is not suddenly a scientist.

Cate Macinnis-Ng and kauri. Photo: supplied.

Kauri dieback is back in the news because Dr Mels Barton has raised the alarm over MPI’s inadequate response to the disease. Kauri in the Waitakere Ranges are declining at an alarming rate with an increase in infection rates from 8% in 2011 to 19% in 2016. Dr Barton says there is not enough communication about the disease and desperately needed research is not being commissioned, despite considerable amounts of funding to MPI.

There is still so much we don’t know about the pathogen that causes kauri dieback or the death process the trees go through. We need to find better ways to contain the disease and effective treatments are desperately needed to prevent continuing declines across the distribution of our most treaured and iconic tree species.

In response to this, artist Sarah Smuts-Kennedy was interviewed by Kim Hill on Saturday Morning. Among other things, Smuts-Kennedy spoke about her time in residence at McCahon House last year. In the interview and on the McCahon House website, she describes a ritual used by Peruvian banana farmers in the 1980s and 90s to combat a fungal infection that was devastating banana crops. Kauri trees infected with kauri dieback at McCahon House were subjected to the same procedure by the artist.

The ritual, known as Agnihotra, is “a process of purification of the atmosphere through the agency of fire prepared in a copper pyramid tuned to the biorhythms of nature corresponding to sunrise and sunset”. Organic cow dung is burnt within the copper pyramid and the fire is timed to “peak” at the exact moment that the sun rises or sets. Combined with a precisely timed mantra, the custom will “recalibrate the atmosphere” within a 750-metre diameter and 12 kilometres up from the ritual site. It’s supposed to influence the cellular structure of plants by elongating them and enabling them to absorb nutrients more readily. Ash from the burnt dung was made into a paste that was painted onto the trees every two weeks. Check out the photo of a tree smeared with dung ash.

An Agnihotra ‘healing’ kit as marketed by an Australian website

What? I don’t know where to start on all of this but let’s just say that, unsurprisingly, I wasn’t able to find any substantiated references confirming the effectiveness of this technique, apart from a citation to an obscure conference titled “Brain storming conference on Bringing Homa Organic Farming into main stream of Indian Agriculture System” from 2008, which has not been peer-reviewed. In other words, there is no evidence that this ritual works because it hasn’t been scientifically tested. Yet it has been labelled a “super science” on the McCahon House website.

I don’t even know what a super science is. Is it science on super foods? I think we can be pretty sure that it’s just a huge pile of steaming organic cow dung. Has it harmed the trees? Probably not – ash from fires can be rejuvenating for plants because it is rich in nutrients (if applied to the soil) but the rest of it has no sound basis. The central issue here is that by using sciencey words and phrases like “super science”, “recalibrate biological systems”, “pathogen”, “the outer cambium of the tree” and “cellular structure”, Smuts-Kennedy is painting herself as an expert in the field but she does not have a science degree. Her Masters of Fine Arts does not qualify her for making claims like this and the mechanisms she describes are completely unsubstantiated. As expected, the ritual has not helped the trees. In her conversation with Hill, Smuts-Kennedy seemed to imply that there were not enough people chanting the mantra or that it didn’t last for long enough during the day. Yeah, right!

Kauri Dieback Station, Tanemahuta. Photo: supplied

Back to the problem of kauri dieback, because it is a huge biosecurity threat. Dr Barton is absolutely correct that more needs to be done. We need to get creative about our approaches and I’m not against trying different things to address this issue. With the recent arrival of myrtle rust, we need to find ways to solve growing numbers of biosecurity problems to conserve our unique species and ecosystems. But setting a pile of dung on fire at specific times of the day and spreading this on trees is highly unlikely to help.

So what should we be doing instead? We have two main lines of attack. The first is proper scientific research tested with established protocols so we can work out if the approach is actually working (rather than using anecdotal evidence and mumbo-jumbo). Current out of the box research funded by the Biological Heritage National Science Challenge includes a project led by Dr Monica Gerth at Otago University looking at how the microbes that cause kauri dieback find the trees and the Kauri Rescue project that is equipping private land owners to treat infected kauri on their land with phosphite. Longevity of infected trees seems to be improved with phosphite but it’s important to note that this treatment does not cure trees. We need more projects like these that are looking at different aspects of the biological processes of survival, mortality and physiology of both the pathogen and the host.

The second line of attack is traditional knowledge. Mātauranga Māori has been developed over decades and centuries of observations as information and understanding are passed from one generation to the next. This traditional wisdom includes knowledge and understanding of both the seen and the unseen. In this excellent documentary, Dr Ocean Mercier explains how mātauranga Māori enhances our understanding of kauri dieback disease. In some ways, mātauranga Māori is developed using methods consistent with the scientific method so for best results, better communication and collaboration between experts in science and mātauranga will be a powerful tool.

Trounson Kauri Park. Photo: supplied

Importantly, the current best line of defence against kauri dieback is prevention of spread. We can all help reduce the incidence of future kauri dieback by carefully cleaning and spraying shoes, other gear and dog paws when going into and leaving kauri forest. This is particularly important at this time of year when tracks are muddy. Stay on the track in all kauri forest, keep your dog on a lead and spread the word to friends and whanau.

You can also contribute to the conservation of the species by purchasing your own tree from the McCahon House Museum.

On a final note, at the end of the interview, Kim Hill asked Sarah Smut-Kennedy about her views on vaccination. Trained medical professionals are the only people from whom the media should seek advice on vaccination.

Cate Macinnis-Ng is a Senior Lecturer in the School of Biological Sciences at the University of Auckland. Her research specialty is tree physiology. Her research focus is responses of kauri water use and carbon uptake to climatic variation. Cate is currently running the kauri drought experiment to define the likely impacts of increasing frequency and severity of drought on kauri trees.

The Spinoff’s science content is made possible thanks to the support of The MacDiarmid Institute for Advanced Materials and Nanotechnology, a national institute devoted to scientific research.

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