Non-native Abies species as alternatives to Abies alba in a changing climate in southwestern Germany: Evidence from species trials

In the context of climate change, the proportion of conifers in Central European forests is projected to decrease with far-reaching consequences for forestry and timber industries. In addition, the loss of native conifers will impact on the dependent biodiversity. To address this challenge, this study examined the growth performance of various alternative Abies species from southeastern Europe ( A. nordmanniana, A. bornmuelleriana, A. equi-trojani and A. cephalonica ) as potential candidate species for southwestern Germany. An extensive dataset for these species was compiled from existing cultivation trials, complemented by growth data on Abies alba and Pseudotsuga menziesii , which were used as reference species. However, owing to the limited extent of the database for A. cephalonica and A. equi-trojani it was not possible to obtain statistically robust results for these species. Height growth of A. bornmuelleriana and A. nordmanniana was comparable to that of the indigenous A. alba . Under comparable site conditions, their total volume production exceeded, in some cases, significantly that of A. alba , but was inferior to P. menziesii . The past growth performance combined with negligible mortality of these Abies spp. from southeastern Europe indicates considerable potential as alternative conifer species Results for A. bornmuelleriana and A. nordmanniana demonstrate clearly that these are high-performing alternative conifer species in terms of height development and total volume production in southern Germany and presumably in other central European regions. Further research should address their response to extreme climatic events and their potential to support native biodiversity. • Non-native, southeastern Abies spp, show great potential in southern Germany focus on climatic and silvicultural suitability criteria. • A unique dataset describing the growth of southeastern Abies species was created for this study. • bornmuelleriana and A. nordmanniana demonstrate that they can be high-performance alternative conifer species in southern Germany. • Height growth of A. bornmuelleriana and A. nordmanniana is comparable to the indigenous A. alba, and • their total volume production was, in some cases, significantly higher than that of A. alba