Botany Outing to the Pelouses des Grandes Fontaines, Bléré

Botanists looking at grass.

On Sunday 18 May the Association de Botanique et de Mycologie de Sainte Maure de Touraine met for an outing at the Pelouses des Grandes Fontaines near Bléré. The main objective was to see the limestone grassland orchids, but like all limestone grasslands, there are many other special plants there.

Adonis Blue butterflies Polyommatus bellargus were abundant on the site. This one is female.

It's quite a big site (70 ha), on two dry rolling slopes with a depression cutting through the middle that is much wetter due to the presence of springs. These springs, which feed a small stream called the Herpenty, also supply the town of Bléré with its water, thus the site is protected by the local authority to maintain the high quality of the water. As a nature reserve the site is not fertilized and it is forbidden to dump any sort of waste there.  The plants and soil bacteria on the site help purify the water that falls as rain into the system, by filtering out for their own use such pollutants as nitrates, phosphates and organic material.

This abundance of plantlife is growing in soil only a few centimetres deep. The underlying limestone breaks through in patches (eg on the left) allowing you to see just how thin the soil is.

These dry grasslands weren't always in such good condition. They have undergone a period of carefully managed natural regeneration. They will always have to be managed if the grassland is to remain. The natural succession is for bushes and scrub to take over. As a consequence the site is mowed and grazed (by sheep and horses) as appropriate, and the invasion of scrub is kept to a minimum. Thus the grassland offers a sanctuary to many species that are threatened or have disappeared from other places. It is rather similar habitat to the Puys du Chinonais that the club visited two years ago.

A Green-underside Blue butterfly Glaucopsyche alexis -- an exciting new species for me and a chalk grassland specialist like the Adonis Blues.

Brome grass dominates the dry limestone grassland which was once used as pasture, before the days of intensive arable farming in the area. On one side of the site there are hundreds of Pyramidal Orchids Anacamptis pyramidalis. My friend Jean, a formidable botanist, commented to me that this protected species, which is a species more commonly encountered in the south, is extending its range and increasing in abundance because it favours dry slopes such as motorway embankments. Orchid seed is so light the turbulence created by passing vehicles can carry seeds as far as 50 km to establish new colonies.

Amethyst Broomrape Orobanche amethystea, a parasite of Field Eryngo Eryngium campestre, seen here clearly associated with its host. This was another exciting first for me. Broomrapes are notoriously tricky to tell apart and this one could easily be confused with Common Broomrape O. minor.

One of the other members of the club told me a great story, nothing to do with the site. He lives next door to the pharmacy in his town and in France people are encouraged to take fungi to the pharmacist to be identified and pronounced safe to eat. Paul, my friend, happens to be a fungi expert, so the pharmacist often calls him in to confirm an identification. He says that its got to the stage where locals are not just bringing in fungi, but all sorts of natural history for identification. The other day he was called in to identify a mating pair of Great Peacock moths Saturnia pyri. He doesn't mind -- he's retired, he is pleased people are interested enough to ask, and he got some great photos.

 One of the many Pyramidal Orchids on the site.
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French Expression: Oui s'il vous/te plaît = yes please. This is the expression to use if you want seconds of dessert or more to drink. Saying 'oui merci' will likely get you passed over as 'yes thank you' doesn't exist in French, having been interpreted as meaning 'thank you, I've had sufficient'.