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We report the results of a post-fire regeneration study concerning an adult Aleppo pine forest, destroyed by fire during summer 2007. The area was subsequently hit by a violent downpour that caused flooding, leading to soil erosion and depletion of the post-fire soil seed bank. Post-fire regeneration of pine in promptly cleared areas was compared with areas where the clearance of the burnt plants was carried out after about eighteen months, in compliance both with regulations governing protected areas according to Italian Law no. 394 of 6 December 1991 and with the area being designated a Site of Community Importance (SCI), in accordance with the European Commission Habitats Directive 92/43/EEC. The surveys in question covered a period of about four years. Keyword: P.halepensis Mill.,Mediterranean ecosystem, forest fire, forest management, post-fire regeneration. 1. PRELIMINARY REMARKS AND AIM OF THE WORK The role of fire as an ecological factor for numerous forest ecosystems, including those of the Mediterranean area, is widely acknowledged (Kozlowski and Ahlgren 1974, Naveh 1975, Pons and Thinon 1987, Pyne 1995, Pausas and Vallejo 1999). Several experimental surveys carried out in the last 30 years have concerned the effects of forest fires on Aleppo pine (Pinus halepensis Mill.) forests in the Mediterranean area (Trabaud et al. 1985, Moravec 1990, Saracino et al. 1993, MartínezSánchez et al. 1995, Ne'eman et al. 1995, Martínez-Sánchez et al. 1996, Herranz et al. 1997). The Aleppo pine is known to be a species which necessarily reproduces by seed dispersal (Trabaud 1987): in the event of a fire the opening of the cones and release of a large quantity of seed leads, in most cases, to prompt and abundant regeneration. Pine seed germination occurs between the beginning of autumn and late winter, which in most environments with a Mediterranean climate represents the rainy period, often associated with mild temperatures conducive to germination. The presence of serotinous cones in the canopy is another feature of the Aleppo pine which must be considered a fireadaptive trait (Daskalakou and Thanos 1996). Each tree produces both serotinous and non-serotinous cones: the former remain closed for several years after maturation and open thanks to the heat of fire, or under the action of warm dry winds which are not at all uncommon in the Mediterranean area (Nathan et al. 1999, Nathan and Ne’eman 2000). Thus the canopy seed bank of the fire-damaged stand is increased in the post-fire phases (Goubits et al. 2003). Research has highlighted the results of different options of silvicultural management concerning natural post-fire regeneration (Ne’eman et al. 1993, Saracino and Leone 1993, Martínez-Sánchez et al. 1999, Leone et al. 2000, De las Heras et al. 2002, De las Heras et al. 2004). Indeed, the post-fire regeneration of Aleppo pine can undergo strong quantitative variations both on a regional and local scale, leading even to temporary disappearance of pinewoods in numerous areas of the Mediterranean basin (Tsitsoni 1997, Pausas et al. 2004). In such cases, the forest manager has to take measures both to identify ways to ensure that pine seedlings take root and become established, and identify possible areas where the low intensity of regeneration could require direct additional interventions (sowing or plantations) in the subsequent phases of environmental restoration. In light of the above considerations, post-fire restoration represents a widely discussed issue both in Italy and abroad. The Italian regulations governing the sector, given a history of widespread illegal building, aim to penalise speculative action on fire-damaged forests and pastures and prevent Orazio la Marca et al. International Journal of Forestry and Horticulture (IJFH) Page 10 wildfires from being profitable activities (according to Art.10, Law no. 353 of 21 November 2000). For this specific case, it is important to underline that the first paragraph of the above-mentioned law bans “ for five years, on the above-cited stands, activities of reforestation and environmental engineering supported with public funds, except under specific authorization given by the Minister for the Environment, for natural protected state areas, or by the competent region, in other cases, for documented situations of hydrological degradation and in situations where an intervention for the protection of certain environmental and landscape values is urgent. It also bans pasturage and hunting for ten years, only for the stands of the fire-damaged wooded areas”. These are important regulations to protect the woods themselves, meriting some reflection. Traditionally, in numerous areas of the Mediterranean basin, one of the very first post-fire operations carried out to re-establish damaged pinewoods regards the cutting down and removal of the plants, totally or severely fire-damaged, whose justification lies in the following reasons: i. dragging the logs on the ground, when the burnt wood is hauled out, facilitates the germination of pine seedlings, since it enhances contact between the seeds which survived the fire and the soil; ii. the removal of the dead plants greatly reduces the proliferation risk of xylophagous insects, which could attack the surviving plants (as actually occurred, in the case of this study, with Tomicus piniperda L.) or negatively affect the survival of the future pinewood. However, some studies carried out on the matter have shown that the removal of the dead plants would have a negative effect on the establishment and survival of the pine seedlings, since: i. leaving the dead plants standing would bring about the release of a further quantity of seed, which would supplement seed dispersal which normally occurs due to heat; ii. even in the event of total destruction of the needles constituting the foliage, the trunks and the branches would perform a shading action, albeit slight, thereby reducing insolation and hence mortality of the seedlings during summer (Ne’eman et al. 1993, Saracino and Leone 1993). These are two different options (cutting down and removing the plants whose vitality is compromised by the fire, or leaving the plants where they are and postponing the operation to some future date) which often create ideological conflict both among academics and technical staff called upon to express opinions about feasible interventions to restore fire-damaged pinewoods. A third option could be to cut down the burnt trees and leave the single prunings, or brushwood and logs, which could well serve a multiple function: release of additional quantities of seeds, provision of seedling shade, and soil protection against runoff caused by heavy rains, especially in steeply sloping areas (Moreira et al. 2011). This would also avoid damage to regeneration after the felling and extraction of dead trees. This research reports the results of the survey carried out in an area of the Gargano Promontory in south-eastern Italy (Municipality of Peschici, Puglia, 41°57′ lat. N, 16°1′ long. E, Fig. 1), devastated by a wildfire in July 2007. In particular, we describe the results achieved in terms of natural regeneration by adopting different silvicultural options. Fig 1. In the circle the Gargano promontory; in red the territory of Peschici (Puglia, southern Italy) Post-Fire Regeneration in P. halepensis Mill. Adult Forests of the Gargano Promontory (Puglia, Italy) International Journal of Forestry and Horticulture (IJFH) Page 11 2. THE CASE STUDY According to the Official Gazette no. 85 of the Puglia Regional Authority published on 28/08/1998 in the period 1974-1994 in the territory of Peschici about 23 forest fires on average were recorded every year. Throughout the province of Foggia, Peschici comes second (after Vieste, with about 32 fires every year) in terms of wildfire frequency. The average area damaged per fire in the above-mentioned period was 13.25 hectares. The statistical data (Leone and Lovreglio 2003) show that huge wildfires have occurred in the Gargano Promontory for at least several decades, especially in the territories of Peschici and Vieste. The above data should be considered in connection with the expansion of pinewoods in the Gargano, located mostly along the coastline and in the immediate hinterland from Vico del Gargano to Mattinata and Monte Sant'Angelo and which, according to Agostini (1964), amounted to nearly 7,150 ha, while according to Mastelloni (1980) it amounted to 8,070 ha subdivided into 39 nuclei. Barbone (1988) reports a completely different pinewood area (about 14,800 ha) which includes approximately 2,300 ha of plantations and forest restoration carried out after the occurrence of wildfires. The period of greatest impact of the phenomenon of forest fires, typical of Mediterranean areas, coincides with the hottest and driest months. In descending order of impact, August is the most severe (37.78%), followed by July (34.11%), September (13.19%) and June (8.66%). On July 24, 2007 an enormous wildfire swept through the area of Peschici, one of the most beautiful in the Gargano Promontory and a popular tourist destination. The fire, exacerbated by a prolonged drought, by high temperatures (the temperature recorded at 10 am was close to 40 °C), and above all by the exceptional wind speed that day (about 20 m per second), caused the destruction of hundreds of hectares of pinewoods (pure stands or mainly of Pinus halepensis Mill.) and of Mediterranean maquis. The images obtained with the multi-spectral sensor Modis placed on the satellite Aqua clearly show that: i. in the Gargano Promontory, and in the regions of Molise and Abruzzo there were several contemporaneous fires which created difficulties for the authorities in charge of monitoring and extinguishing fires (red hot-spot in the IR image of Fig. 2); ii. the seriousness of the phenomena which occurred in the Gargano was undoubtedly exacerbated by the wind speed, as sh