The stakes are higher than they might sound. Both authors, working in close collaboration, published the same names for alliances and associations of plants in the same year, including familiar and widely used names such as Adenostylion, Nardion, Genisteto-Vaccinion, Arrhenatherion, Caricion fuscae and Cardamineto-Montion. Under Article 33 of the nomenclatural code, names published simultaneously and identically are treated as homonyms of equal age, and the principle of priority cannot separate them. For nearly a century, classification schemes such as the EuroVegChecklist and the Prodromus of French Vegetations had simply chosen Braun-Blanquet’s names by convention. The new research turns that convention into documented fact, and it voids one of the code’s own worked examples, which used the 1926 pair as the illustration of homonyms of equal age.

The key evidence came from the Revue d’Auvergne, the journal of the Society of Friends of the University of Clermont-Ferrand, which carried the proceedings of a joint 1924 phytosociological excursion in a series of booklets called Arvernia. The second booklet contained Braun-Blanquet’s article on the complex climax of alpine heaths in the Cantal, titled Le climax complexe des landes alpines. Because the booklet had no library record of its own and was issued in three parts across different issues of the journal, its effective publication date had never been pinned down. The researchers hunted through Auvergne libraries for the society’s 1926 financial statement, which they found in the departmental archives at Aurillac, presented to members on 10 February 1927.

That balance sheet proved decisive. The invoices for issues 4 to 7 of volume 41 were filed separately and in chronological order, showing that four issues of the journal appeared in 1926, one per quarter. The first issue of the year, issue 4, contained pages 1 to 48 of Arvernia 2, including Braun-Blanquet’s article on pages 29 to 48. The remaining articles and the photographic plates followed in issues 5 and 6. The unavoidable conclusion is that Braun-Blanquet’s paper was published in the first quarter of 1926, establishing a firm terminus for the rivalry.

Luquet’s thesis, Essai sur la géographie botanique de l’Auvergne, tells a more intricate story. A handwritten note on the archived copy records the defense date of 12 June 1926, yet two printed stamps dated 8 July 1925, one from the dean and one from the rector, show that the manuscript had been approved for printing a year earlier. Under French academic practice of the era, however, candidates could not distribute their theses until the official defense. The code itself is explicit that publications become effective by distribution of printed matter, so even if the thesis was printed before June, it cannot count as effectively published earlier. Archival traces confirm this: the Natural History Society of Auvergne’s session records from July 1926 make no mention of the thesis, while the January 1927 session notes its publication, placing distribution between July and December 1926.

Complicating the picture, Luquet also published an article in 1926 in an Alpine geography journal, an Esquisse phytosociologique du massif des Monts-Dore, citing the same association names as his thesis. But this text carries no quantitative information on the listed species, so under Articles 2b and 7 of the code it is not validly published for nomenclatural purposes and plays no role in the priority question. The authors also propose a corrected citation for Braun-Blanquet’s elusive article, recommending that it be referenced as appearing in Arvernia 2 within volume 41, issue 4 of the Revue d’Auvergne, pages 29 to 48.

The close collaboration between the two men explains how they came to publish identical names simultaneously. Herbarium specimens in Montpellier and Clermont-Ferrand, traceable through the ReColNat database, document them collecting together in the Monts-Dore in May 1920 and on joint excursions over the following three years. In his thesis, Luquet thanked Braun-Blanquet for asking him, during the spring of 1920, to study the vegetation of the Dore mountains. In July 1923 Braun-Blanquet travelled alone to the Cantal, where he collected Veronica urticifolia at the type locality of what became the association Adenostylo alliariae-Cicerbitetum alpinae, and in August he returned to visit Luquet. It was evidently then that they planned the 1924 excursion whose results would collide on the printed page two years later.

The nomenclatural fallout is substantial. Adenostylion alliariae, proposed for conservation, now rests on Braun-Blanquet’s priority, with Luquet’s version a later illegitimate homonym. Arrhenatherion elatioris was validly published by Koch in March 1926, even before Braun-Blanquet, so it too precludes Luquet’s name. Cardamino-Montion, long attributed to Braun-Blanquet’s 1926 article, actually first appeared in his 1925 methodological work, and the authors note a proposal to reject it as ambiguous in favour of Philonotidion seriatae. For the Nardion strictae, the authors reject a mistaken lectotypification based on a Luquet relevé and restore Braun-Blanquet’s own single published relevé as the holotype. The Genisto pilosae-Vaccinion receives a new, effective lectotypification on the association Genisto pilosae-Callunetum vulgaris, one of the two associations in the original diagnosis, replacing an ineffective earlier choice.

Other names required different treatments. Caricion nigrae, traditionally accepted for acidophilic small-sedge fens, is shown to have a baso-neutrophilic type under Koch’s concept, and the authors suggest that conserving Braun-Blanquet’s Caricion fuscae of the same year would sidestep the controversy, since its holotype association is unambiguously acidophilous. Festucion variae turned out to be invalid as published in 1926 because its namesake Festuca varia was absent from the only relevé, and the name was only validated by Guinochet in 1938. Luquet’s Piceion excelsae, validly published and with priority over the familiar Piceion abietis of Pawłowski and colleagues from 1928, is nonetheless proposed for rejection in favour of the widely used later name, a formal request to be presented to the nomenclature committee. Finally, Sphagnion fuscae and Luquet’s Sphagnion are both naked names without quantitative diagnoses, leaving Sphagnion medii from 1933 as the correct name for acid Sphagnum bog vegetation. Taken together, the study demonstrates how patient archival work, from budget lines to handwritten defense dates and herbarium labels, can still resolve questions that have shaped vegetation science for a hundred years.

Subject of Research: Publication priority and nomenclatural status of plant community names published in 1926 by Braun-Blanquet and Luquet

Article Title: Nomenclatural and syntaxonomic note regarding the anteriority between the publications of the year 1926 by J. Braun-Blanquet and A. Luquet

Article References: Roux, C., Thébaud, G., & Theurillat, J.-P. (2026). Nomenclatural and syntaxonomic note regarding the anteriority between the publications of the year 1926 by J. Braun-Blanquet and A. Luquet. Vegetation Classification and Survey, 7, 83-93. https://doi.org/10.3897/vcs.171300

Image Credits: AI Generated

DOI: 10.3897/VCS.171300

Keywords: phytosociology, nomenclature, ICPN, Braun-Blanquet, Luquet, Auvergne, plant communities, syntaxonomy, publication priority, herbaria, vegetation classification, Massif central