Key message Phenology is of increasing interest to climate change science and adaptation ecology. Here, we provide bud development, leafing, and leaf senescence data, collected on 772 European beech and silver fir trees between 2006 and 2019 on Mont Ventoux, France. Dataset access is at https://doi.org/10.15454/TRFMZN . Associated metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/a33c8375-9a90-4bc3-a0d7-19317160b68f .

Key Message We provide phenotypic and genotypic data for a progeny trial of 5813 European beech seedlings, originating from 60 open-pollinated families collected at three altitudes (1020 m; 1140 m, 1340 m) on Mont Ventoux (44° 11′ N; 17° 5′ E).

Motivation: Trait variation within species can reveal plastic and/or genetic responses to environmental gradients, and may indicate where local adaptation has occurred. Here, we present a dataset of rangewide variation in leaf traits from seven of the most ecologically and economically important tree species in Europe. Sample collection and trait assessment are embedded in the GenTree project (EU-Horizon 2020), which aims at characterizing the genetic and phenotypic variability of forest tree species to optimize the management and sustainable use of forest genetic resources. Our dataset captures substantial intra- and interspecific leaf phenotypic variability, and provides valuable information for studying the relationship between ecosystem func-tioning and trait variability of individuals, and the response and resilience of species to environmental changes. Main types of variable contained: We chose morphological and chemical characters linked to trade-offs between acquisition and conservation of resources and water use, namely specific leaf area, leaf size, carbon and nitrogen content and their ratio, and the isotopic signature of stable isotope 13C and 15N in leaves. Spatial location and grain: We surveyed between 18 and 22 populations per species, 141 in total, across Europe. Time period: Leaf sampling took place between 2016 and 2017. Major taxa and level of measurement: We sampled at least 25 individuals in each population, 3,569 trees in total, and measured traits in 35,755 leaves from seven European tree species, i.e. the conifers Picea abies, Pinus pinaster and Pinus sylvestris, and the broadleaves Betula pendula, Fagus sylvatica, Populus nigra and Quercus petraea. Software format: The data files are in ASCII text, tab delimited, not compressed.

Background: Progress in the field of evolutionary forest ecology has been hampered by the huge challenge of phenotyping trees across their ranges in their natural environments, and the limitation in high-resolution environmental information. Findings: The GenTree Platform contains phenotypic and environmental data from 4,959 trees from 12 ecologically and economically important European forest tree species: Abies alba Mill. (silver fir), Betula pendula Roth. (silver birch), Fagus sylvatica L. (European beech), Picea abies (L.) H. Karst (Norway spruce), Pinus cembra L. (Swiss stone pine), Pinus halepensis Mill. (Aleppo pine), Pinus nigra Arnold (European black pine), Pinus pinaster Aiton (maritime pine), Pinus sylvestris L. (Scots pine), Populus nigra L. (European black poplar), Taxus baccata L. (English yew), and Quercus petraea (Matt.) Liebl. (sessile oak). Phenotypic (height, diameter at breast height, crown size, bark thickness, biomass, straightness, forking, branch angle, fructification), regeneration, environmental in situ measurements (soil depth, vegetation cover, competition indices), and environmental modeling data extracted by using bilinear interpolation accounting for surrounding conditions of each tree (precipitation, temperature, insolation, drought indices) were obtained from trees in 194 sites covering the species' geographic ranges and reflecting local environmental gradients. Conclusion: The GenTree Platform is a new resource for investigating ecological and evolutionary processes in forest trees. The coherent phenotyping and environmental characterization across 12 species in their European ranges allow for a wide range of analyses from forest ecologists, conservationists, and macro-ecologists. Also, the data here presented can be linked to the GenTree Dendroecological collection, the GenTree Leaf Trait collection, and the GenTree Genomic collection presented elsewhere, which together build the largest evolutionary forest ecology data collection available.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

La rapidite du changement climatique (CC) en cours, l’incertitude des modeles climatiques et la diversite des reponses des especes au CC motivent la communaute scientifique a accroitre le volume des observations et a acquerir des donnees de qualite. Parmi celles-ci, la phenologie du debourrement chez les especes ligneuses requiert une attention particuliere. En effet, ce facteur majeur de l’adaptation n’a pas encore devoile tous ses secrets et notamment pour les especes photosensibles, le hetre en l’occurrence, potentiellement soumises dans un avenir tres proche a un manque d’exposition aux temperatures froides pour lever la dormance. C’est pourquoi, la communaute, notamment a travers le SOERE TEMPO, se mobilise, afin de standardiser les materiels et methodes utilises pour etudier les determinants environnementaux impliques dans cette phase de developpement, qu’est le debourrement. Parmi les dispositifs utilises, les chambres climatiques qui permettent un controle fin des conditions de lumiere, temperature et humidite afin de tester des hypotheses jouent un role tres important. La maitrise de la programmation et de la caracterisation de l’environnement de ces chambres est capitale. Nous proposons dans cet article d’explorer comment la photoperiode doit etre apprehendee dans les experiences sur le debourrement des plantes ligneuses mobilisant de telles chambres. Nous avons pu montrer, (i) qu’il est primordial d’operer avec une intensite lumineuse et une photoperiode minimales pour obtenir un taux de debourrement et une duree moyenne de debourrement necessaires a l’appreciation de la levee de dormance, et (ii) que la technologie LED est une tres bonne alternative pour etudier ces processus et mettre en coherence les etudes et les actions de minimisation de l’impact du CC en cours, du fait des economies d’energie importantes qu’elle permet de faire. Et ce d’autant plus, que cette technologie innovante pourrait nous permettre d’aller plus loin et plus rapidement vers un front de sciences, survole ici, l’implication d’autres longueurs d’onde que celles autour du rouge clair dans la reponse des plantes a la lumiere pour le debourrement chez les plantes ligneuses. En ce sens, l’echantillonnage pratique nous a permis de montrer (iii) que la difference de seuil ou de sensibilite aux temperatures dans le temps pourrait expliquer le caractere precoce ou tardif des genotypes observes a l’echelle d’une population et (iv) que la difference de conditions lumineuses au moment de la formation du bourgeon au-dessus et en dessous de la canopee n’induit pas de reponse differente aux conditions environnementales en phase de sortie de dormance.