Mortality of Different <i>Populus</i> Genotypes in Recently Established Mixed Short Rotation Coppice with <i>Robinia pseudoacacia</i> L.

• Main Authors: Jessica Rebola-Lichtenberg, Peter Schall, Peter Annighöfer, Christian Ammer, Ludger Leinemann, Andrea Polle, Dejuan Euring
• Format: Article
• Language: English
• Published: MDPI AG 2019-05-01
• Series: Forests
• Subjects: short rotation coppice; poplar; black locust; survival rate; mortality; mixing effect
• Online Access: https://www.mdpi.com/1999-4907/10/5/410

Short rotation coppices play an increasing role in providing wooden biomass for energy. Mixing fast-growing tree species in short rotation coppices may result in complementary effects and increased yield. The aim of this study was to analyze the effect on mortality of eight different poplar genotypes (<i>Populus</i> sp.) in mixed short rotation coppices with three different provenances of the N-fixing tree species black locust (<i>Robinia pseudoacacia</i> L.). Pure and mixed stands were established at two sites of contrasting fertility. Survival of poplar was assessed for each tree two times a year, for a period of three years. In the first two years, high variation in mortality was observed between the genotypes, but no significant differences between pure and mixed stands were identified. However, three years after planting, higher mortality rates were observed in the mixtures across all poplar genotypes in comparison to pure stands. The expected advantage on growth of combining an N-fixing tree with an N-demanding tree species, such as poplar, was overshadowed by the <i>Robinia</i>&#8217;s dominance and competitiveness.