Kew Comes to the Vallee de la Claise Tourangelle

The Kew team's vehicle, parked at Les Limornières, where they stayed.

Photo courtesy of Nicole Crawford, Les Limornières.

For the past year I have been involved in a project to study the Red Helleborine Cephalanthera rubra. This orchid is critically endangered in Britain and the project's primary goal is to save the species in the British Isles. It is a joint effort by the National Trust, who own and manage the remaining Red Helleborine sites, the Royal Botanic Gardens, Kew, who are attempting to propagate the species, and Natural England, who are providing the funding.

The target species, Red Helleborine Cephalanthera rubra.

The reason I am involved is because project members wanted to check out Red Helleborines in France, where there are several areas where the species thrives here. Because I have written about the orchids here one of the National Trust wardens got in touch and arranged a study trip last year with two colleagues. After their very successful visit Jon Kendon from Kew got in touch to ask if I could help with a proposed visit of his team in 2016.

Downy Oak Quercus pubescens woodland and prime Red Helleborine habitat.

The Kew research team is led by Dr Viswambharan Sarasan. Jonathan Kendon, who co-ordinated the trip with me, is the lab technician, and the third member of the team is Dr Kaz Yokoyo, who is research assistant. The aim of their work is to isolate the fungi present in the roots of the French Red Helleborines and establish if they can be used to aid the germination and growth of English Red Helleborine seed. This is the sort of work they focus on in their lab at Kew, working with plants from all over the world. For a good overview of a typical project that they've contributed to, see Kaz's blog post about the conservation of orchids in Madagascar.

The Kew visit was a lot more complicated to organise than the National Trust visit because it involved taking samples of a protected species. We had to approach the appropriate authorities and Jon had to submit an official written submission asking for permission to take plant material. My job was to find out who exactly we needed to contact at the Préfecture and liaise with property owners and local French botanists. This turned out to be more time consuming that we had anticipated, and the Kew team had to reschedule their visit because of funding issues as well.

The Kew team begin their investigation by just looking.

One of the first things I did was contact my friend Marc Fleury, a local orchid expert. He had helped with the previous visit of National Trust wardens, suggesting sites and getting landowner permission. He and I scoped out the sites prior to the English visits in both cases. This time round Marc also helped where I had to approach landowners formally, by correcting my French and designing a consent form that we sent to the landowners. I did the legwork of getting names and addresses for the landowners by visiting the relevant town halls and asking to check the cadastral records. I also got in touch with everyone I could think of who might have an interest in the project to let them know what was planned (that included the botany section of the university at Tours, the Conservatoire d'espaces naturel Centre Val de Loire, the local representative of the Société Française d'Orchidophilie, a local journalist and my local botany club).

Jonathan Kendon (left) records the details as Dr Viswambharan Sarasan (right) takes a sample.

The Prefectural permission to take plant material took weeks to be granted but eventually it was and we set the date for fieldwork as 7 June. Marc, Jean Bouton and I went out the week before to check the sites. That was a day or two before the floods peaked. We got absolutely saturated and had to go 10 kilometres out of our way to find bridges we could cross to access the site we thought would be best for the fieldwork to be undertaken. We were disappointed by what we saw too. There weren't many Red Helleborines in flower and we were worried the Kew team wouldn't find enough material. To top it off, we ran into the mayor of Chaumussay out inspecting the flood and she had a bit of a rant. Fortunately not directed at us, but at the Prefecture, who had not bothered to ask her opinion before granting Kew permission to take samples from a protected plant growing on her patch. Luckily I had kept her informed about progress and had forwarded the Prefectural documentation to her, so I was in her good books. Marc was in her good books because he was organising an orchid walk for a group from Amboise and raising the profile of Chaumussay and its reputation as an orchid hotspot.

Jon measures root depth while Dr Kaz Yokoya takes a photographic record with his phone.

This group from Amboise turned out to indirectly cause us a slight problem. Four days before the Kew team arrived I realised there had been some confusion regarding permission from the landowner of the site we wanted to use. I was working so I asked Marc to call on the landowner and clarify who was visiting the site, when and what it was that they were doing. He went round to her home but there was no one around. He couldn't follow it up because he was going on holiday. Finally, the day before the Kew team arrived I managed to catch her at home, sort out the problem and reassure her that there would be no damage to the site, and we would do our best not to disturb the game.

Kaz checking a fragment of root to identify what species it belongs to.

On the morning of 7 June I got up early and was down at the baker's in the Grande Rue by 7.30 am, collecting ham and cheese baguettes for lunch and croissants for breakfast. Having picked up the day's provisions I headed over to Les Limornières where the Kew team were staying. After breakfast together we drove over to Chaumussay, where we were to meet Jean Bouton, who had volunteered to represent French botanists. Jean Pelle, another orchid associate was with him and he admitted that Marc had called him and asked him to be there in case there was further negotiating to do with the landowner. Marc clearly was nervous that my French wouldn't cut it with the landowner.

Sarasan cutting a sample of a suitable Red Helleborine root.

Off we went to the site, via a farm track that had been badly scoured out by the rain. The best patch of Red Helleborine is very conveniently situated by a very distinctive tree. The Jeans told us it was probably about 400 years old and a hybrid of Downy Oak Quercus pubescens and Pyrenean Oak Q. pyrenaica.

Sarasan gently sorting out roots in the soil. The abundant ivy roots were a problem.

The Kew team spent ages just looking at the patch of orchids and discussing what their approach should be. They didn't want to dive right in to the middle of the patch, but to choose small plants that were isolated or on the edge of the main group. There was two reasons for this. First, it would minimise the disturbance to the main patch. Second, taking some samples which were further away from the main patch would mean they were more likely to be seedlings, not clones, which might make a difference to the range of fungi living in symbiosis with the orchids.

Sarasan and Jon measure the root depth of a specimen.

Taking a sample from the path.

The team worked slowly and carefully in a number of places across the site near Chaumussay and took about ten samples. They were aiming to get protocormes of the orchids and roots which they could slice up in the lab to see what mycorrhizae would grow. The mycorrhizae are embedded in the cells of the orchid roots in bundles known as pelotons and the plant depends on them to transfer minerals and nitrogen from the soil (in return for which the fungi receives carbohydrates). They also took soil samples and a seedling Downy Oak and a tiny Juniper Juniperus communis, to examine if all the plants are using the same mycorrhizae. From what they said, it seems likely that Red Helleborine likes to position itself underground on the horizon between the humus rich layer and the underlying limestone. There was a considerable difference between the length of samples taken about a third of the way up the slope, growing in deep leaf litter and those taken at the top of the ridge, in the thin sandstone layer or the flinty soil. A plant from lower down the slope had roots 15 cm under the surface, a plant from up at the top only had its roots 5 cm down.

Taking a sample from the top of the limestone ridge, which has a remnant sandy cap.

At one point in the morning the husband of the site owner turned up, almost certainly to check exactly what we were up to. Jean Pelle stepped forward to greet him and introduce him and I realised there was a very specific reason why Marc had arranged for him to be there. Turns out that Jean was our visitor's college teacher (thirty or forty years ago) and has known him all his life. 

I must say that I would never have been able to negotiate the sometimes delicate relationships with the various French parties involved without the help of Marc and the Jeans. I'm very grateful to them and I know the Kew team are too. The project would never have got this far without Marc and Jean Pelle's local knowledge, and Jean Bouton's willingness to represent French botanists on the day of the field work.

Sarasan tells me that this research has implications for other terrestrial plants that are facing extinction. They hope to be able to isolate fungal material and use it to improve seed germination and growth. They should be able to tell if they've got something after 48 hours in the lab, but it could take months to identify the specific mycorrhizae and a year write up their results. The hope is that the results will enable the Red Helleborine conservation project to move to the next stage and start propagating a new generation of the orchid with English material. The team were very happy with what they collected and delighted with the site. Marc and I needn't have worried that there wouldn't be enough for them to make the trip worthwhile.

I had a most interesting day out in the field with them and loved watching the careful way they worked and how well they worked as a team. From them the Jeans and I learnt that orchid roots have a particular smell, a bit starchy and lightly sulphurous, somewhat like a potato. Kaz could identify tiny pieces of orchid root by touch, sight and smell -- that was impressive. Jon pointed out that the target species always seems to have a red stem, whereas other similar orchids nearby did not, something I had never noticed. This year most of the plants were not in flower but were little seedlings or clones with just a few leaves. Marc thinks this lack of flowering was due to the dry spring last year. (Remember that last year in the first week of June when the National Trust team were here we had temperatures in the 30s!) Given how much rain we've had this spring I am expecting a bumper crop of flowers next year!! The Kew team had hoped to do some hand pollination while here, as a sort of payback for taking a few plants away, but the flowers proved too fragile and Jon couldn't do it. A shame, but the population seems robust enough here anyway.

Once again, the lesson for me was a reminder not to take the abundance of orchids in the Claise Valley for granted. Jon had never seen a Lady Orchid Orchis purpurea in the wild before, and here we had a couple of splendid ones still looking good. The landowner was bemused that we were so interested in what to her is a fairly ordinary plot of land. She loves it and is proud to be the guardian of the orchids and other wildlife, but I think she doesn't really realise how special her former sheep fold and limestone ridge overlooking the Muanne is.

Further reading: A Perfect Day in Panzoult.

Saving the Red Helleborine.

Red Helleborine Research Report.