Observations from traditional provenance trials used in forestry were difficult to generalize because they have been limited to a small number of provenances of the species that were tested at one or few particular locations. Thus, they lacked scalability and predictability across the species current and future range, especially at the species range margins. In this experiment, the performance of various provenances and families is evaluated across a wide range of environments, thus findings can be generalized. In the coming 30 months, observations from the hundreds of micro-gardens across Europe will be combined together and with genomic data to draw general conclusions about the climate adaptedness of provenances and families. The ultimate goal of this project is to estimate the reaction norms of different populations and lineages in terms of early life-history traits across a large range of environments, including extremes, where fitness drops to zero. Reaction norms summarize the phenotypic expression of a genetic unit, and have been rarely estimated in across more than two natural environments, let alone the species range. This experiment will us to obtain an unprecedented number of observations across a wide–range of genetic units (lineages, populations, families) and environments. Further, using the genomic data, we will be able to estimate the genetic similarity between populations and families, and using the interpolated environmental data, the environmental similarity between garden locations. This information will be incorporated to a genomic prediction model, and used for predicting the breeding values of mother trees (genetic merit evaluated by their offspring) and the average performance of populations in untested environments. Thereby, we will be able to estimate most missing gene–environment combinations. The prediction tool will be presented as a web-tool; the first version is expected in 2026.
