Protection and conservation of the manna ash landscape in Sicily

Abstract

Known as manna ashes, some local varieties of Fraxinus ornus L. and F. angustifolia Vahl (Oleaceae) are cultivated for extracting the manna, a product rich in mannose which is useful under both pharmaceutical and nutraceutical aspects. As wild plants in Sicily these ashes participate in diversifying evergreen and deciduous oak woods as well as other forest communities at the watercourse borders, together with several species of Salix, Populus and Ulmus, particularly in the hills. Cultivation of manna dates back to ancient times in Sicily and elsewhere and ash groves were increasingly spread up to the half of last century. Then, the culture had a progressive decline due to the abandonment of land and its gradual replacement by other crops. Most of the surface formerly occupied by ashes is now uncultivated and therefore also exposed to recurrent fires. As a consequence even the rich varietal heritage, documented by detailed monographs, went partially lost, although recently have not missed a revival of the local scientific community.In the face of the many thousands hectares occupied by these crops in the past, now residual plantations are confined in just a few hundred hectares in the territories of Castelbuono and Pollina (province of Palermo), in the northern side of the Madonie mountains. In this area the plant landscape had been strongly characterized by the ash groves, that besides acted an efficacious hydrogeological protection. At present, despite the progressive loss, the cultivation of manna ashes could still play an important role in the local economy. Therefore, in order to preserve all social, cultural and even biological values as well the landscape, it was proposed to establish a natural reserve of the manna ashes some decades ago; but that suggestion was later abandoned after the Madonie natural Park was estasblished. Nevertheless the Park has not, over the years, affected concretely the further abandonment of ash groves and the protection and conservation of the related landscape. Recently, the Sicilian Regional government has adopted some measures aimed at supporting farmers for replanting ash groves: these are active conservation initiatives for the produc- tion of manna. Here we find it useful to propose even passive measures such as reforestation like those implemented elsewhere in the province of Palermo with good results for the envi- ronment and landscape. Other initiatives, that could not be postponed, concern vocational training as well as research and conservation of ash varieties germplasm to be grown in specific arboretums such as those already implanted in the fields of the agricultural schools at Castelbuono (Palermo) and Mussomeli (Caltanissetta) and in the experimental plantations at Sparacia (Caltanissetta), SAF Department of the Palermo University.