“Ilots de senescence� (islands of senescence) A concepts born in France and Switzerland with applications to protected areas of Nature 2000 network
DEFINITION: IdS is a deliberately abandoned area to spontaneous evolution (the complete collapse of trees and recovery of forest dynamics. It should not be confused with the "islet of aging" that is created only temporarily (and managed with a silvicultural objective). Area of an IdS: up to 20 ha (usually 5-10 ha) IdS should represent from 2% to 10% of the whole forest
The IdS provide habitats that improve the "naturalness" of forests: presence of large and old trees and dead wood.
These sites are not themselves managed; this "non-management" is an integral part of the management plan and is currently applied in Switzerland, in Communal forests, and in France, in the Nature 2000 network.
The first experiment in Italy is under the Life+ project ManFor CBD (LIFE09 ENV/IT/000078, 2010-2015) in Cansiglio (North Italy) in a beech forest (shelterwood) and Natura 2000 site. (Action Responsible F. Mason)
Natura 2000 contracts In France, the State compensate an owner that leaves unmanaged a group of trees for 30 years. The contract terms (N trees, diameter, etc.) are defined at regional level. It represents the only financial compensation for the establishment of an island of senescence.