Chapter 13: Rejuvenating the elderly and aging the youngsters: ancient management practices in continuously renewed native ash tree forests in the High Atlas of Morocco

Didier Genin (1, 2)

1 LPED - Laboratoire Population-Environnement-Développement
2 IRD - Institut de Recherche pour le Développement

Rural forests are types of forests where biological and cultural aspects continuously intermix to conform specific forests whose structures and functioning reflect local livelihoods. They usually are the result of an ancient cohabitation between trees and human beings, made of exploitation and conservation, and the cumulative development of a rich vernacular knowledge. In the Moroccan High Atlas, trees play several roles for local agropastoral populations who have shaped their forests in order to cope to diversified needs, particularly those for construction material and forage supply during the Autumn, but also who have adapted to specific biological traits of trees they have to deal with. Trees and forests constitute hence a highly valuable patrimony for these human communities. The native ash tree (Fraxinus dimorpha) stands naturally found in the northern slopes illustrate this closed interrelationship. Peoples have secularly shaped ash tree stands by sequentially trimming and pollarding individual trees. The most characteristic figure is the presence of old individuals with big twisted trunks, that are regularly pollarded. They are the testimony of a long trajectory of use and shaping trees characterized by: 1) highly rigorous 4-year cycles of exploitation of pollarded trees, which allow to harvest each individual tree for foliar forage after 4-years regrowths, and at the same time to shape and let some well-growing branches develop for other cycles in order to provide diameter-standardized poles and beams for house-roof making; and, 2) the management of tree regeneration, particularly the protection of overgrazed trees, by mean of stone walls, and the selection and linkage of the most vigorous resprouts, in order to favor trunk anastomosis. This practice allows an improvement of foliage production by 31% after a 4-year cycle, with respect to non-anastomosed trees. These culturally modified living trees provide evidence of human adaptation to the environment and a legacy of traditional knowledge and management systems, through selection and manipulation of individual trees, and by modifying ecosystems. This situation offers 1) an alternative basis of thinking of what could be a sound forest management, far from the classical forestry approach, and, 2) original insights for conserving ancient anthropized forest ecosystems.

Mots clés: Culturally modified Trees; practices; traditional ecological knowledge; High Atlas; Morocco

Domaines: Environnement et Société; Sciences de l'Homme et Société; Anthropologie sociale et ethnologie

Didier Genin. Chapter 13: Rejuvenating the elderly and aging the youngsters: ancient management practices in continuously renewed native ash tree forests in the High Atlas of Morocco. Sandrine Paradis-Grenouillet; Chantal Aspe; Sylvain Burri. Into the woods: Overlapping perspectives on thehistory of ancient forests, Editeur Quae, 2018, 978-2-7592-2907-9. ⟨hal-02095703⟩