Torre Guaceto
Name of the project area: ancient olive groves of Torre Guaceto Main land uses and ownership status of the project area: The ancient olive groves of Torre Guaceto Reserve concern only the area of Carovigno; they are sited in a welldefined strip, bounded by the railway line on the last hillsides, upstream of the SCI area Macchia S. Giovanni. They stretch for about 260 ha (equal to 1/4 of the area of the whole Reserve). The centuries-old olive plants belong to the variety Ogliarola Salentina, with some specimens of the variety Cellina di Nardò. The whole area sited in the territory of Carovigno falls within the Scheme of the PDO extra-virgin olive oil “Collina di Brindisi” and in the Route of the extra-virgin olive oil “Collina di Brindisi”. Of great historical and nature value is the tree-lined broad avenue joining the Castle of Terranova to the bay of Torre Guaceto. Along the above road there is still the windbreak made up of the original shrublands, with huge specimens of wild olive, holm oak, lentisk, buckthorn and Phyllyrea tree. Land tenure is characterised by fragmentation due to the splitting up and allocation of holdings to peasant families at the time of Land Reform, and to hereditary succession. The mean farm size is about 2 hectares compared to the original 5 and/or 10 ha, which were considered as the “minimum production unit” at the time of Land Reform. The extreme land fragmentation is today one of the reasons of economic non-sustainability of the agricultural activities of this area. In this framework there are large estates covering several hundred hectares. All the actions proposed in the project are sited in Torre Guaceto.
The area of ancient olive groves falls within the scheme of the State Nature Reserve of Torre Guaceto; it covers an area of 260 ha that is sited on the last hillsides of Murge, and lays over a shallow clay-textured soil covering a calcareous substrate. The area constitutes a bio-geographic boundary between the area of Murge and the plain of Brindisi. It includes a regularly-spaced olive grove that is 500 years old, on average, planted after the building of Guaceto Aragonese Tower that ensured a greater protection of the coast and of inland areas. The prevailing variety is Ogliarola salentina that represents in Apulia the ancient plants. Over the last decades some groves were rethickened, some deteriorating plants were substituted by the local cultivars such as Cellina di Nardò. The ripening of both cultivars is staggered so that the harvest period lasts from November till February. The olive grove is mostly run in dry farming, and plants keep their size and original canopy volumes nearly unchanged with second, third and fourth order branches.
In the project area there are problems related to the mismanagement resulting in: - the groundwater pollution, due to the use of copper (Haignon et al. 2002, Besnard et al 2001) and other heavy metals in the fertilization (admitted by EU Reg. 2092/91 for Organic Agriculture) responsible also for direct damages to soil-borne microrganisms (Banu N.A. et al 2004), - the removal of hedges, dry walls and other small-scale structural elements that act as major shelter areas for many target species of the project, - the presence of residues in the olive oil produced; for example the use of rotenone for the control of olive fly releases residues that are the direct cause of Parkinson ‘s disease (Cabras, P., Caboni, P., Cabras, M. , Angioni, A., e Russo, M., 2002 - Sherer, T.B., Betarbet, R., Testa, C.M., Seo, B.B., Richardson, J.R., Kim, J.H., Miller, G.W., Yagi, T., Matsuno-Yagi, ., e Greenamyre, J.T., 2003). - the impoverishment of the agro-ecosystem and of its self-regulating capacity, - the disappearance of beneficial insects (Psyttalia concolor, Eupelmus urozonus, Pnigalio agraules, Eurytoma martellii) the presence of which is related to hedges of myrtle (Myrtus communis), honey locust (Gleditschia triacanthos), mastic (Pistacia lentiscus), caper (Capparis spinosa) and jujub (Zyziphus sativa). In particular Psyttalia concolor is harmful to the main olive pest, that is the olive fly (Bractrocera oleae). The disappear of beneficial insects (Psyttalia concolor, Eupelmus urozonus,Pnigalio agraules,Eurytoma martellii) due to both the chemical treatments and the low density of hedges, as: Myrtle (Myrtus communis), Acacia (Gleditschia triacanthos), lentisk (Pistacia lentiscus), Caper (Capparis spinosa) and Jujube (Zyziphus sativa). In particular, Psyttalia concolor is antagonist of the main pest of the olive tree, like the olive fly (Bractrocera oleae). The genetic importance of ancient olive plants derives from their ability to cope with adverse weather conditions and climate changes over the centuries. The reduction of genetic variability is indeed one of the problems threatening severely the balance of agro-ecosystems. The conservation and propagation by the nursery techniques of existing genotypes is of paramount importance, both for the preservation of genetic resources ( with high risk of genetic erosion) and for starting the genetic improvement, as well as to obtain plants for re-establishment in the areas with ancient olive trees.