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Dynamics of natural regeneration in Pinus laricio stands from Southern Apennines (Italy).) and large (1520 m 2 ) gaps created in calabrian pine (Pinus laricio Poiret ) stands (mean height 22 m) in the Southern Apennine. After three growing seasons first results put in evidence: a) no significant differences of water soil content were observed between gap sizes; b) transmittance was higher in large and medium gaps than in small ones and in the centre and northern sides in both gap sizes; c) calabrian pine seedling density was higher in large gaps than in medium and small ones and namely in the centre positions; silver fir seedlings appear after the second growing season in small and medium gaps; d) seedling mortality of calabrian pine was relevant in small and medium gaps in the edge and silver fir seedling mortality in the centre of the large ones; e) in these first years the ground vegetation (bramble and bracken) represents a moderate detrimental effect on seedlings establishment that could be removed by partial cuttings.Keywords: Renaturalization, regeneration, conifer stand, gaps, microclimate. IntroduzioneIn Italia sono stati eseguiti numerosi rimboschimenti con conifere, la maggior parte con pini, a scopo essenzialmente protettivo. Molti di questi rimboschimenti mostrano gravi problemi di stabilità (meccanica e biologica) di fronte agli agenti meteorici (venti, tempeste) e suscettibilità ad attacchi di funghi patogeni e insetti.La rinaturalizzazione delle monocolture di conifere (qui intesa come la trasformazione in popolamenti con una maggiore diversità compositiva e strutturale) rappresenta uno dei principali obiettivi della selvicoltura in Italia e in molti Paesi europei (Heitz &