Guidelines for the choice of forest reproductive material in the face of climate change

Due to the long-lived nature of trees, silviculture is a practice
that takes a long-term perspective. In a context of rapid projected
climate changes, forest managers need to find ways to take
decisions about the long-term management of forest stands
without complete knowledge about what future conditions will be
like. Existing knowledge does not allow us to determine precisely
whether a close-to-nature approach (which relies on spontaneous,
natural processes) or proactive interventions in forest regeneration
is better suited to fostering adaptation in forest ecosystems.
Adaptation is the micro-evolutionary process enhancing the fitness
of a population in accordance with the environmental conditions.
One idea that has been proposed is human-assisted transfer of tree
populations, guided by projections of future climate conditions,
but it has not been widely accepted in Europe, partly because of
uncertainties about the results of this approach and partly because
climate changes have so far affected Europe to a lower extent than
other regions, such as North America.
The present guidelines focus on issues related to the choice of
forest reproductive material (FRM) in the face of climate change,
based on knowledge generated by field studies and modelling.
The objective is not to single out the most appropriate approach,
valid in all conditions, but rather to present most recent research
findings to support decision-making and analysis by forest
managers, conservationists and field ecologists.