Trials too slow for dying stands
#00074
Multi-decade species trials produce reliable data only after 20–40 years, but many forests are dying now. There is no mechanism to give foresters actionable guidance on the timescale at which they actually need to make replanting decisions.
Parent issue
#00071 Test new species and provenances
Location
global
Description
RENEssences and similar long-term species trials are scientifically rigorous: dozens of species and provenances grown side by side, monitored for survival, growth, pest resistance, and frost tolerance over multiple decades. The results that come out of them are trustworthy precisely because they take this long.
The problem is that foresters in the Grand Est and elsewhere need to make replanting decisions every year. A communal forest that lost its spruce in 2018 is being replanted right now, in 2026, with whichever species the local ONF agent thinks has the best chance — and that decision will not be validated by trial data until 2046 at the earliest. By then it will be too late to reverse a bad choice. There is currently no formalized process for translating partial, in-progress trial results into shorter-term recommendations, and no fallback if the species chosen today turns out to be wrong.