Health status of the cork oak stands of Annaba region: Case of the Hedough forest (Algeria)

Abstract: Health problems of Algerian cork forests back to the beginning of the last century following the emergence of the phenomenon of decline. The cork oak forests of Eastern Algeria escape this situation. We set up in 2010-2011 two permanent observation stations (Sidi-El-Temmem and Berouaga) in the Edough forest to study the health status and different decline factors of cork oak. We conducted dendrometric measures (girth taken at 1.30 m from the ground, tree height and height of first branches), and cork statements (height and number of debarking, debarking coefficient) on 80 trees. During the fall of 2011 we evaluated the health status of the stands by examining crown and trunk, bark and subcortical area. Trees have on average 10 m high, 1.5 m in circumference, 1.8 m in debarking heigth. Over 52% have a low defoliation and 30% low leaf discoloration; calculated decay index indicates a stand at the beginning of decline (Id = 1.80). The lichenous flora (fruticose lichens and foliose) is present on all the trunks. Few trees have carbonaceous crusts, runny or dehiscent cork surfaces while insect holes are visible over 80% of the sampled trees. Human impact remains limited despite 30% of the trees present injuries.