“…In fact, we found evidence that tree diversity effects on herbivory were dependent on climate. This result could partly explain the variable effects of tree diversity on herbivory previously reported in the literature (Brezzi et al, 2017;Castagneyrol et al, 2014;Jactel et al, 2020;Kambach et al, 2016;Ratcliffe et al, 2017;Schuldt et al, 2010Schuldt et al, , 2014Vehviläinen et al, 2007;Wein et al, 2016) including in studies focusing on birch trees (Castagneyrol et al, 2018;Haase et al, 2015;Muiruri et al, 2019;Setiawan et al, 2014). Specifically, we provided evidence for changes in associational effects along the mean annual temperature gradient: associational resistance of birch to insect herbivory occurred in cold conditions, whereas no associational effects could be detected in warm conditions.…”