Seed regeneration of sweet chestnut (Castanea sativa Miller) under different coppicing approaches

• Published in: Forest ecology and management 2020-09, Vol.472, p.118273, Article 118273
• Main Authors: Marcolin, Enrico, Manetti, Maria Chiara, Pelleri, Francesco, Conedera, Marco, Pezzatti, Gianni Boris, Lingua, Emanuele, Pividori, Mario
• Format: Article
• Language: English
• Subjects: Chestnut coppice; Chestnut recruitment; Seedlings growth
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/j.foreco.2020.118273

•Natural seed regeneration of chestnut is a key issue in recovering overaging chestnut coppices.•The establishment of seed regeneration was more than sufficient to guarantee a safe turnover of dead stools.•Chestnut trees released (standards) after coppicing do not play a relevant role as tree-seeders.•The presence of standards inhibited the growth of seedlings up to 10 m away.•An excessive presence of standards has promoted the settling of regeneration of shade-tolerant species. The management of Italian chestnut coppices has gradually been suspended after World War II, causing a widespread overaging of the concerned stands. In recent years, the renewed interest in coppice wood products increased the need of a solid knowledge on the most suitable restoration practices of overaged coppices. In this context, a key issue is assuring a qualitative and abundant seed regeneration of the chestnut tree (Castanea sativa Miller) in order to substitute overaged stools. Open questions still exist however on the role of the standards (trees released after coppicing) and, in particular, on their interaction with the post-coppicing establishment of seed regeneration. In order to clarify these aspects, we applied different coppicing systems in overaged chestnut coppices so as to create a gradient of residual coverage ranging from full coverage left (no intervention) to simple coppicing (all trees cut, no standards released). The impact of different treatments on chestnut regeneration has been then assessed through field surveys in the second and fifth year post-coppicing, respectively. Chestnut seed regeneration promptly and abundantly established to guarantee the replacement of dead stools also in the simple coppicing. The post-coppicing pulse of chestnut seed regeneration mostly originated from the existing annual seed bank and it was concentrated in the first two years after the intervention, whereas seed inputs by standards or by adult trees at the forest edge played a secondary or negligible role from the third post-coppicing year onwards. Thus, the presence of standards did not benefit regeneration. Rather, it displayed a marked depressive effect on the growth rate of young chestnut seedlings and, under significant shading conditions, enhanced the establishment of shade-tolerant tree species. From a silvicultural point of view, simple coppicing of overaged chestnut coppices represents a valuable management option combining a rapid establishment of natural seed regen