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Monday, 29 April 2013

Is there a role for plant-based medicine in our modern society?


What is the first image that comes to mind when you read the words “plant-based medicine”? This is the question James Wong presented the audience with last Thursday night at the 5th annual Annals of Botany Lecture held at the University of Bristol.

The audience, admittedly filled with plant aficionados, came up with answers such as aspirin and morphine. However, the same question posed during a university course that Wong teaches came up with some different imagery: dread locks and muddy boots, fads and big business, witch doctors in the Amazon, and cauldrons and concoctions. Imagery that suggests that plant-based medicine is a system of health care that is impractical, ineffective and therefore irrelevant. Given these cultural perceptions, is there still a role for plant-based medicine in an age where we are constructing nanoparticles and running quantum algorithms?

Wong spent well over an hour exploring this question with an audience of over 200 last week – dispelling many of the myths that surround herbal medicine and distinguishing between scientific fact and cultural belief. But before I get to that, let me tell you a little bit about the man himself.

A self-proclaimed botany geek

If you’re not already familiar with the infectious smile of James Wong and his unbridled enthusiasm, let me introduce you. James is an ethnobotanist. He studies the relationships between plants and people - how people use plants, how they learn about what plants do, and how plants are perceived across societies.  He trained at Kew Gardens and his own research into traditional medical systems has taken him to Ecuador, Southern Chile and Indonesia.

You may recognise James from the award-winning BBC Two series Grow Your Own Drugs and as a member of the BBC One Countryfile team. If that’s not enough, he’s also an award-winning garden designer and best-selling author. His energy level makes me think that he may have a very thorough understanding of some of the stimulant properties of plants, but as I’m working my way through my fourth cup of tea this morning, who am I to talk!

Drawing a thick black line between conventional and herbal medicine

James puts up a picture of a pile of pills on the left hand side of the screen and a picture of herbs on the right. These represent conventional and herbal medicine accordingly. James then uses some very opposing language to describe perceptions about these two schools of medicine – synthetic vs natural, evidence-based vs ineffective, proven safe vs potentially dangerous. Then, he draws a thick black line between the two.

“In the western world,” says James, “people in one camp immediately dismiss the other camp. But this idea is not scientifically based, it’s a cultural perception. Most scientists don’t see this black line. They are concerned about the efficacy of a substance rather than the source.”

For starters, many pills are derived from plants. In fact, 50% of the most commonly used conventional drugs and 75% of current cancer treatments are derived from natural sources. James provides a couple of fantastic examples:
·         Houttuynia cordata – is given as an injection treatment- known as HCI –as a treatment for severe acute respiratory syndrome (SARS) because of its anti-inflammatory properties.
·         Artemisinin is isolated from the plant Artemisia annua, sweet wormwood, and is taken as an antimalarial, replacing many of the quinine-based antimalarials.

So why is it that with so many medicines combating some of the toughest diseases of the 21st century coming from natural sources, there is still a perception that herbal medicines are best left for those that dance barefoot in the mud at Glastonbury?

Myth 1: Herbal medicines are ineffective

Reason 1: lack of evidence

The number one reason that herbal medicines are thought to be ineffective is due to a lack of evidence. James sites cost as the main reason that evidence lacks for these herbal remedies. With an estimated 50,000 medicinal plant species on the planet, James estimates that it would cost between USD $4.5 trillion and 36 trillion to test all these potential plant species (assuming we’ve actually found them) for the 300 most common ailments. This is 81 years of the world’s combined GDP. Not only is this unrealistic, there is very little economic incentive to even try to test all medicinal plants as patenting plant sources is very difficult.

The other challenge with providing evidence for the effectiveness of herbal medicines is that much of the testing is, quite frankly, inaccurate. James uses Echinacea as a classic example of this. In a study looking at the efficacy of Echinacea, they tested the dried leaves and flowers of E. purpurea – the common garden species. However, it is the fresh root of E. pallida and E. angustifolia that is used in traditional medicines.

“This is like testing the fur of a kitten to determine the effectiveness of the claws of a tiger,” says James.

James also referred to a paradigm mismatch as the root of these perceptions.   We are products of our paradigm environments. You and I fully understand the concept of germs because we were raised in that paradigm. However, think about someone from an isolated tribe in the Amazon grappling with the idea that we have little creatures living on and in us that grow and multiply simply by dividing in two and can make us sick. It’s simply not plausible to them!

Morning glory seeds mashed up have mind-altering effects. It was once mainstream to use this powerful hallucinogen during psychoanalysis. The patient, in an altered state, would talk about issues that would otherwise be suppressed and then the psychoanalyst would be able to help interpret these ramblings and resolve the patient’s problems. In Latin America, the seeds are used in much the same way, except replace the psychoanalyst with a shaman and the mind-altered state is an opportunity to seek advice from spirit guides; same medicinal plant, but two very different paradigms.

We also seem to forget that the food we put in our mouth is, indeed, medicine. The prunes I gave my son yesterday...very effective...and I don’t need three clinical trials to confirm that!

Reason 2: loss of traditional medical knowledge

The second main reason for the myth that herbal medicines are ineffective is that there has been an incredible loss of traditional medical knowledge. When the Spaniards arrived, they brought with them disease that wiped out 70% of the indigenous people of what is now Ecuador and with this, much of the traditional knowledge.

Along with disease, the European visitors carried exotic seed that thrived in the new habitat that they created as they deforested the land.  Today, 90% of medicinal plants in Ecuador are hedgerow species from Spain. The indigenous people had to learn about the uses of these new plants that were now far more convenient than the small isolated populations of their traditional medicinal plants. It was then the knowledge of these new exotic species that was passed down to the next generations.

Reason 3: many herbal medicines simply do not work

Sadly, a few bad seeds with some overly-stated advertising can ruin it for an entire industry. James uses the anti-oxidant powers of pomegranates as an example. Yes, pomegranate does have relatively high levels of anti-oxidants, but in fact, no more than say an apple.

Myth 2: Herbal medicines are impractical

At this point, James returned the discussion back to food and how everything we eat has some biological effect on our bodies...those four cups of tea I had this morning certainly have! Lunch, for example, might include a curry, a couple of fig bars, a piece of chocolate and a cup of coffee.  In our body, this breaks down to antiseptic (onion) and decongestant (chili) in the curry, laxative (fig) in the fig bars, psychoactive (chocolate), and stimulant (caffeine). I don’t know about you, but eating has never been an impractical task for me!

To address this public perception of impracticality, many companies have packaged herbal medicines up in sterile looking ways in order to give the appearance of being synthesised drugs. A brand of IBS relief capsules, for example, is no more than a peppermint jelly when the ingredients are examined. An analgesic cream is simply refined capsaicin taken from chilies.

So, does herbal medicine still have a role to play in our age of information and technology?

“It does still have a role to play,” says James, “because we still eat and because we still use plants as the base for many of the drugs in use.”

In fact, James claims that the UK is now the world’s biggest grower of daffodils. The flowers aren’t for display purposes, they are grown for a stress hormone they produce known as galanthamine. The drug is very effective in the treatment of the symptoms of Alzheimer’s. The soil conditions in Wales are apparently ideal for stressing these lovely spring flowers into producing the hormone in abundance!

James’ final thought of the evening was that it’s not really a matter of whether herbal medicine still has a role to play, “it’s a matter of whether you wish to accept it.”

If you have an opportunity to listen to James Wong speak, I highly recommend it. He is both entertaining and educational .

A reminder that Sunday May 19th is Fascination of Plants Day at the Botanic Garden. There will be interactive displays, a plant hunt and garden tours running from 10am to 4:30pm. Find out more at the garden’s events page http://www.bristol.ac.uk/botanic-garden/events/2013/84.html

Thursday, 25 April 2013

Weaving Ethel: How the Botanic Garden is bringing moas back to life


Last week I met Ethel. I’m not sure what image that name conjures up for you – perhaps it is the gutsy singer Ethel Merman or the eccentric EastEnders character Ethel Skinner. For me, I immediately think of Lucille Ball’s sidekick character Ethel Mertz in the old American sitcom I Love Lucy. It seems that Ethel is one of those names that summons a big personality, and the Botanic Garden’s Ethel is no exception. Of course, this might be due in part to her impressive stature at nearly 8 feet in height.

Ethel is a new willow sculpture currently under construction at the Botanic Garden. She is the first of two moa birds that will be on display among the native New Zealand plants in the garden. Despite her towering height, Ethel is going to be the smaller of the two birds, with the other giant expected to stand closer to 12 feet tall. The sculpture was named by her creator, Sally Meadows, who has been working two days a week on the ambitious project since February.

“Ethel had to be a female,” explains Sally, “because the female moas were much bigger than the males. It’s one of the biggest size differences known among bird species.”
Ethel is the first of two moa bird willow sculptures to
be displayed at the Botanic Garden later this year.

The plight of the moa

Moas are an extinct group of flightless birds that were endemic to New Zealand until they were driven to extinction. There were nine species all together, and the largest of the species, Dinornis robustus and Dinornis novaezelandiae, could reach heights of 12 ft and are estimated to have weighed around 500 lb.

Artist renditions of the birds look very similar to an emu, with feathers that have evolved to look more like fur, broad feet and sturdy legs built for running, and a long neck for browsing foliage. While originally it was thought that moas stood with very upright necks, much like emus and ostriches, a more complete analysis of their bone structure suggests that it was more likely that they held their heads in a more forward position.

The ancestral moa species was thought to arrive on New Zealand approximately 60 million years ago (Mya). A sparse fossil record prior to 6 Mya leaves many ambiguities about the early evolution of moa species. However, it is thought that numerous species had evolved on both the North and South Islands and then at around 22 Mya, during the Oligocene drowning, those inhabiting the North Island went extinct as the land mass was below sea level. Those on the South Island took refuge on the land that remained above sea level (only about 18% of the current land mass of New Zealand) and then are thought to have recolonised the North Island again about two million years later.

Prior to the arrival of humans, the moa’s only known predator was the Haast’s Eagle, which had a wingspan that was just shy of 10 ft and weighed a notable 33 lbs. However, as a result of hunting, habitat loss and a slow population regeneration time, all species of moa were driven to extinction by the first Polynesian settlers, ancestors of the Māori, by around 1400 AD.

The tall tree with foliage only at the
top is mature lancewood (Pseudopanax
crassifolius
) - the immature plant can
be seen in the lower right corner.

Plants adapt to the selective pressures of tall grazing moas

Moas were grazing herbivores and analysis of the beaks suggests they were likely very effective ones; Pachyornis elephantopus is thought to have been able to slice through 8mm diameter twigs with its secateurs-like beak.

However, one native New Zealand plant that evolved significant defences against these grazers is the horoeka or lancewood (Pseudopanax crassifolius). For the first 20 years or so of its life, this tree has a series of very long, narrow, leathery leaves that have a very prominent central vein and serrated edges.  The leaves come off the narrow spindly stem and point downwards, which essentially resembles a spindly palm tree with knives pointing out in all directions. I imagine this would not be a herbivore’s first choice, even with secateurs for a beak.

Yet, as the plant matures it begins to transform its shape and appearance entirely. The lancewood eventually begins to form branches at the top and the new leaves lose their serrated edges and become wider and shorter. The hypothesis is that this species coevolved with the moa and once the plant surpassed the height of these grazers it shifted its strategy from a moa defense to a photosynthesizing offense; broader leaves on branches would be far better at harnessing the sun’s energy than the narrow downward facing leaves it had earlier in its life.
The immature lancewood has evolved
highly unpalatable leaves.

Ethel’s taller sister will eventually stand majestically near the Botanic Garden’s lancewood trees – a wonderful memory of an evolutionary arms race.

So how does one weave an 8’ tall moa out of willow?

When Sally shows me into the potting shed, Ethel is dramatically suspended by a number of ropes from the rafters. This enables Sally to move her up and down to work on different parts and to lift her out of the way if the gardeners need the extra space. However, with her head and neck complete, most of her body frame in place, and some temporary legs for stability, she is becoming increasingly less mobile.

Sally had taken a weekend willow weaving course at the Botanic Garden and had helped Vicky, a Botanical Horticulturist, do some demonstrations at last year’s sculpture exhibition in the garden. So, when she realised she was going to be made redundant in her job, she spoke to the garden’s curator, Nick Wray, about helping out with the moa project. The next thing she knew she was in charge of weaving the giant bird.

“I like doing creative things,” said Sally, “and my work in the past hasn’t offered me this.”

At the core of the sculpture is chicken wire that runs through the body and up the neck to provide extra strength. The overall 3D shape of the sculpture is due to a frame of different sized willow rings. The rings are then joined together by lengths of willow that are woven through the circles to give longitudinal support as well as provide a framework for weaving the outside.

Sally gets the willow from Somerset in bundles that are about five feet in length. The willow needs to be
Sally's hands work swiftly as she weaves Ethel's
willow body.
soaked for roughly a day per foot of length. It then needs to be given a couple of days to dry before it can be worked with.

Sally takes a length of willow and clips off a few inches at both the thick end as well as the spindly end. She then runs the willow across her knee, where she is wearing kneepads, to improve the flexibility as well as test it.

“If it’s not properly soaked,” explains Sally, “it will break on my knee and I can either re-soak it or throw it out.”

After the branch has passed the knee test, Sally takes it and pushes it through the woven circular structures of the frame tying it off at one end. Sometimes she uses twist ties to temporarily hold parts together as she works the piece, but these are removed and it is only the winding of willow upon willow that holds the massive sculpture together in the end...oh, and a little chicken wire at the core.

Ethel's head and neck detail is complete.

“In the end, you’re at the mercy of the willow”

Sally points to a spot on the jaw line of the completed head and admits it bothers her. I have no idea what spot she’s talking about because it all looks pretty amazing to me, but she goes on to talk about the fluidity of the art. She works from a plan, but admits that “in the end, you’re at the mercy of the willow”.

Well, she’s not complete yet, but I think Ethel will do her name proud.

Tuesday, 23 April 2013

Seeds of Change volunteers get down and dirty


Last month Alex and Rhiannon wrote about the ballast seed collection at the Botanic Garden and hinted at a new project, called “Seeds of Change: Growing a Living History of Bristol”. The Seeds of Change project provides Bristol schools and community groups with an opportunity to grow ballast seed gardens of their own and link the plants that they grow to the maritime history that is integral to Bristol’s heritage.

The partners on this project, the University of Bristol’s Centre for Public Engagement, Botanic Garden, and Arnolfini have all been working hard on different aspects of the project to prepare for its launch, including developing creative workshops in partnership with artists and academics, building relationships with schools and community groups, sorting out the logistics of planting ballast seed gardens all over the city, and recruiting a troop of student volunteers to go out into the community and help build the gardens. The project is well underway and I recently joined the student volunteers on a training session at the Botanic Garden as they prepared to head out to the schools and community groups.

The day’s training covered everything from advice on how to draw out the many themes of the Seeds of Change project and managing enthusiastic school children to tips on turning soil. However, like all good training, there was a practical component that allowed the volunteers the opportunity to get their hands dirty and pick up some great tips from the staff at the Botanic Garden at the same time!

Avoiding the ‘Tom and Jerry’ style of tool storage

Botanic Garden Curator, Nick Wray
explains tool safety.
After a brief introduction to the day by Seeds of Change Coordinator Martha Crean, and Botanic Garden Curator Nick Wray, the volunteers were divided into two groups. I followed Nick’s group out to the vegetable patch where they were to practice preparing a bed and sowing seed.

After the volunteers put down their gardening tools and gathered around, Nick starts with some basic health and safety. He points to rakes left in what he refers to as the ‘Tom and Jerry’ style. I’m sure you can picture it – stand on the upturned teeth of the rake and the handle springs up to crack you in the nose in a perfectly choreographed slap-stick comedy sketch. Only it’s not slap-stick and it’s school children rather than a cartoon cat and mouse.

Nick masterfully divides and designates, showing how to handle groups by example and taking the volunteers through every step that they will need to do when they go out to their schools and community groups. The volunteers range in gardening experience and so Nick doesn't miss a single detail, explaining how to handle the tools without breaking your back, how to prepare soil that has been turned and broken down to just the perfect particle size, and even how to clean your boots when you’re done.

There are also tips about keeping school children engaged and busy. After he uses the draw hoe to mark out a furrow in the ground that marks the border where they will be planting, Nick says, “Now, you and I can see that but a child won’t. They’ll step right over it.” As a mother, I can immediately see his point, but I wouldn't have thought of it had he not mentioned it. He suggests that the volunteers keep the children busy by getting them to collect pebbles or sticks to lie in the furrow and mark out the planting bed. Simple, but an effective way of keeping everyone engaged with the project.

Nick even manages to work in discussions of evolution as he points out that most of the seed is dark against the soil in order to avoid predation. These are tidbits of information that I would be storing for later if I were one of the volunteers.

And in the potting shed...
Froggie works with Seeds of Change
volunteer Alex in the potting shed.

With Nick’s group all busy sowing seeds, I decide to head back to the potting shed to see what Froggie’s group is doing in the potting shed. I walk in and it’s very quiet and the volunteers are all very busy filling small pots with soil, placing the pots in large trays and using other pots to level the soil, then planting the seeds, watering and placing the trays outside.  I've unfortunately missed the instructional part.

Some of the community groups and schools won’t have garden space, and so they will instead be doing some container gardening with their ballast seeds. The volunteers will have to be prepared for both situations.

Student volunteers share an interest in gardening and children

For the volunteers, Seeds of Change offers a wonderful opportunity to be involved in a city wide project that ties gardening in with themes related to art, history and science, while also building their skill set and network for the future.

While there are many benefits on paper to volunteering, I decided to chat with a number of the volunteers to find out what really brought them away from their studies and research to play in the dirt on a sunny March day.
Seeds of Change volunteers sowing ballast seed in pots.


When I approached Camilla, a second year undergraduate student in Biological Sciences, she was busy breaking down clumps of dirt with a rake in the Garden’s vegetable patch. Camilla worked at the Botanic Garden last year and really enjoyed it, so when the email about the Seeds of Change opportunity hit her Inbox she embraced the opportunity, “I was looking for something to do outside of my studies, but still related,” said Camilla. “It’s a chance to give something back while still learning.”

On the way to the potting shed, I walked with two plant ecology PhD students who are also volunteering for the project. After joking that the project would be a good distraction from their research, they admitted that it was the idea of growing gardens with children that appealed to them.

In the potting shed, Alex, a History of Art student, was busy patting down soil in little pots to provide an even surface for sowing the seeds. Alex is thinking about going into teaching and found the aspect of working with children appealing, but also comes from a family of gardeners and in her words, “is quite used to messing about in the dirt”.

For others, like Nicola, another History of Art student, it was the prospect of making contacts and working with Arnolfini that drew her into the project.

Next steps for the volunteers

Seeds of Change volunteers turning soil, preparing for
when they will help schools and community groups plant
ballast seed gardens all over Bristol.
After the day of training at the Botanic Garden, the volunteers are going out to the site location that they’ve been assigned to with Kasha Smal , who is both a horticulturalist and former primary school teacher.  Kasha has helped produce a workshop program for the Seeds of Change project directed at years 4, 5 and 6 (keystage 2). The workshop includes a 30-minute activity as well as 30-minutes of thinking about the origins of the plants and places they might know as well as uses of the plants.  Kasha will then introduce the idea of planting the ballast seed garden and introduce the volunteer.  The volunteers will take the opportunity to assess what the garden situation is – pots versus a plot, well-worked soil versus needs some work, tools on hand.

After the introductory session, the volunteers will return to their groups on their own and plant the gardens.  Then, a few weeks later, they will do a follow-up session to see how things are getting on and maybe take the opportunity to talk more about the plants that have germinated and link them to the themes of the Seeds of Change project.

Ballast seed garden is only one strand of the project

The project is ambitious. Gardening is only one component of the project as each of these groups will also do a creative workshop alongside the ballast seed garden. There are three workshops to choose from and each one combines an artist and an academic working on some aspect of the Seeds of Change project. When Martha explained each of the workshops to me, the one that caught my attention investigates the sounds of plants and involves a sound artist as well as a scientist. The idea is to explore the sounds you hear when you put a microphone up to a plant and investigate the biological processes that underlie those sounds.  That is most certainly the subject of a future blog post!

There will be a website that will be associated with the Seeds of Change project, and each of the 16 ballast seed gardens being built around the city will have a page within that website with pictures and anecdotes documenting their experiences. I’ll be sure to follow how the project is progressing and report back with news of how the volunteers are getting on.

The Seeds of Change project is still in need of some volunteers, so if you're interested, please contact Martha Crean at 0117 33 18313 or martha.crean@bristol.ac.uk.