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A glance at the mycological flora of the Atlantic coastal area of

South-Western France

 

By Francis Massart

February 2005

 

Broadly speaking the coastal zone includes :

1.                  The dune area (from inland towards the shore, in short) ® a wooded dune, a black and white stable or "lette"[1], an unstable white dune.

2.                  A stretch of a few kilometers with sea-pine plantations often alternating with patches or broad-leaved trees, mostly pedunculate oak-trees , sometimes mixed with various other species, especially near the "crastes"[2], along river banks, by the ponds, near dam places by the roadsides

The presence of these various species of trees : Holm oaks, chestnut oaks, chestnut trees, birch trees, various willows, maple trees, various poplars, glutinous alders, ash-trees, arbutus accounts for the fact this latter zone - which for convenience' sake will be called "inland area – hosts, from spring to fall, a rather varied range of fungi; indeed one can find more species there than under pine-trees.

However, the dune area may, at times, show a rather important range of species, while at this time of the year "the inland area" remains almost unproductive, apart from some species incrusted on trees.

Seasons And Period Of Growth

A large number of species are very constant when it comes to their places and periods of growth although some fungi may – according to meteorological circumstances and other still unknown factors – appear unexpectedly; therefore, one should not be surprised to come across some specimen outside their usual places and period of growth.

Spring: In these environmental surroundings with such particular soil and climatic conditions, springtime, as a rule, does not favour the growth of fungi; however, some species may grow, among which we shall list the most common:

  • On the white dune and sometimes on the grey "lette" , right from the beginning of March the dune Morel, a long-lasting species, maybe symbiotic of sea reeds or some other sand-connected plants, at times, it grows along with Peziza ammophila, these two species may last for a fortnight to three weeks. By the skirt of the grey "lette", at the skirt of the wooded dune, Amanita junquillea, a particularly prolific species which may be present all the year round but for drought or long frosty periods: one may also find, though very rarely, Amanita verna, a toxic deadly species[3], Amanita supravolvata and some small sand-connected species, e.g Psathyrella ammophila, Inocybe heimii, Marasmius littoralis, Mycena chlorantha which can also be seen in the fall.

Summer: Along the coastal belt more than anywhere else, the summertime period brings to a halt the growth of  fungi : to be sure, one can discover a few survivors in the places sheltered from climatic pressure, but this remains a most unlikely prospect.


[1] Lette or lède = a depression of the ground between the dunes.

[2] Crastes = man-made irrigation ditches.

[3] On May 5th 1984, Claude Lanne, spotted on the skirt of the wooded dune at Lacanau-Océan several specimen of a slender form of  Amanita verna (NaOH +) growing in the middle of the sand at a distance of the wooded area. The drawing we show has been made from one of the specimens C.L. gave us. Its outline does remind that of Amanita phalloides  var. larroquei whichwe observed at Le Porge  in the same environmental conditions..

Fall : On the coastal fringe proper, the first signs of the great seasonal growth are to be seen later than inland, where, as mentioned earlier, the broad-leaved trees sites predominate; therefore, under the pine-trees of the wooded dunes, the grey "lette" and the white dune, one can witness late blossoming of a good many species (generally, in November); these are spectacular as well as spontaneous growths.

Winter: It is be no means unusual of the dune for that fall growth to last up the first day of frost; In December and even in January; for some species, a new growth often take place after the first bouts of frost, they may vary in number and density from one year to the next; these changes in the steadfast growth of some species are likely to be party linked to climatic circumstances, but, following a four-decade observation, we think the fact they get scarcer and scarcer has do with the ever increasing number of people visiting these places over the years and consequently intensive  pickings – sometimes for commercial purposes – of edible species, first among these Cantharellus lutescens which is displayed for by the crate in the commercial centres; unfortunately, to the liabilities of human interferences must be added the destruction of non-edible species during these wild quests. Another common species, which also very much coveted, Tricholma auratun, a.k.a. the "Bidaou" - let's not forget this fungus is responsible for several patent and established poisoning among which three resulted in actual deaths – therefore, we advise people who can't refrain from eating this tricholoma, which is rightly considered, as from now, as being potentially dangerous, to absorb only small quantities at reasonable intervals.

            A distinctive feature of the dune and pre-dune fungi flora: some common species, Amanita, Boletus ,Russula, Tricholoma, sometimes have an unusual aspect and uncommon sizes, indeed one is surprised by the size of some specimens growing on a poor in humus substratum, right in the sand and sometimes pretty far from wooded zones. During propitious years, the density of fungi in some places is considerable; the ground is carpeted with Cantharellus lutescens, Hygrophoropsis aurantiaca, host of Amanita muscaria decking the roadsides, a concentretion of various species, Amanita citrina, Amanita  junquillea, Suillus bovines, Suillus luteus, Tricholoma saponaceum, Hebeloma cylindrosporum, Cortinarius mucosus, Cortinarius semisanguineus, Cortinarius obtusus, Russula xerampelina, Russula cessans, Lactarius deliciosus, Lactarius hepaticus, Agaricus augustus, Gyromitra infula, to name a few. In the places where mosses, peatmosses, and lichens thickly carpet the ground, many small and middle-sized species grow, often displaying a disproportionately long stip, very often just a prominence of moss betrays the presence of a fungus.

            In the wake of the more or less common fungi listed over the past four decades, there are several rare or new species, some of them akin to the Mediterranean flora. Our colleague and friend Jacques Guinberteau, an engineer working for the INRA[1], as conducted a long careful study of this dune flora; for the sake or our fellow mycologist, we shall mention of these original or unknown fungi studied, detremined or described by Jacques Guinberteau ® in : La mycoflore des échosytèmes dunaires du Bas-Médoc. J.G. INRA.

Macrolepiota psammophila  Guinb.

Lepiota brunneolilacea Bon& Boiffard

Lepiota sublaevigata Bon & Boiffard

Lepiota ocraceodisca Bon

Limacella subfurnacea contu

Gyrophragnium dunalii (Fr.) Zeller 1943

Stropharia halophila Pac.fo. Occidentalis Courtecuisse,

Bon & Guinberteau

Sericeomyces menieri  (Sacc.) Contu

Bolbitius variicolor  Atk.

Tulostoma kotlabae  Pouzar

Agrocybe pusiola  (Fr.Fr.) Heim

Oudemansiella mediterranea  (Pac. & Lall.) Horak

Rhodocybe malençonii  (Pacioni & Lalli

Alas! We must conclude this brief very incomplete picture on a rather alarming remark: the climate anarchy which has been prevailing for a few years seems to result in the increasing scarcity or even the disappearance of some formerly plentiful species, genus Tricholoma and Cortinarius in particular; in spite of this rather gloomy prospect, the South-Western (Aquitaine ) coastal zone offers to all -  Whether experts or lovers - a huge territory for research and certainly holds in store many surprises for dogged searchers.


[1] INRA : National Institute for Agricultural Research.