Synthesis of the significant impact of shading (S), warming (W), fertilisation (F) and their interactions on the growth of the tundra shrubs <i>Cassiope tetragona</i>, <i>Empetrum hermaphroditum</i> and <i>Betula nana</i>.

+: positive impact; −: negative impact; no effect: manipulations had no significant impact on the growth variable; W×F− and W×F+: lower and higher effects in the combined treatment, respectively, than expected from the single treatments alone; n.a.: no data available; a: years of treatment at the time of measurement; b: non-significant effects are not listed; c: data refer only to the experimental site investigated in this study (the tree-line heath of Paddustieva, Abisko, Northern Sweden) and are derived from earlier published papers and the current work, and d: green biomass as ratio of grey stem biomass.