{"paper_id":"3ea8c0bb-6cb3-4426-bdf3-97ced49464c3","body_text":"Summary\nForest regeneration is shaped by strong demographic filters during germination and early establishment, yet the relative contributions of provenance and environment remain poorly resolved under natural conditions.\nWe combined climate-chamber trials with a continental-scale, field-based citizen science seed-sowing experiment to quantify germination, early phenological development, and three-year post-germination survival fir (Abies spp.) and beech (Fagus spp.) provenances across Europe. Using mixed-effects models and a state-based Markov framework to reconstruct phenological trajectories, we quantified successive demographic filters from seed to established seedling.\nGermination was structured by genotype-by-environment interactions (G × E) in both genera, but with contrasting expression: fir showed broadly parallel environmental responses among provenances and partial concordance between climate-chamber and field, whereas beech showed strong provenance-by-environment responses and weak predictability from controlled conditions. Seed weight was a key axis in beech (lighter seeds germinated more and developed faster), but confounded with geographic differentiation in fir.\nIn contrast to germination, post-establishment survival was dominated by site-level environmental filtering with limited consistent provenance effects, revealing a life-stage shift from fine-scale G × E during germination and early development to broader environmental control of survival—an important consideration for regeneration—based management and assisted migration.\nCompeting Interest Statement\nThe authors have declared no competing interest.\nFootnotes\n↵** Shared senior authorship\nhttps://github.com/kcsillery/MyGardenOfTrees_PilotTrials/tree/main","source_license":"CC-BY-4.0","license_restricted":false}