Table 1. List of publications and studied tree species used for the meta-analyses, assessing effect sizes of moose exclusion on seedling density and height. Abbreviations for tree genera or species refer to Table 2.
Author(s) Year Tree genus or species used in the analyses Location
1 Angell & Kielland 2009 SALIX Alaska, USA
2 Faison et al. 2016 DECID Massachusetts, USA
3 Heikkilä et al. 2003 BETULA, PICEA, PINSYL, SALIX, SORBUS C Finland
4 Heikkilä & Tuominen 2009 BETULA, PICEA, PINSYL, POPTRE S Finland
5 Hidding et al. 2013 ABIBAL, BETULA, PICEA, POPTRE, PRUPEN Quebec, CAN
6 Jensen et al. 2012 QUERCUS S Sweden
7 Kielland & Bryant 1998 SALIX Alaska, USA
8 Kolstad et al. 2018 BETULA, PICEA, PINSYL, SORBUS S and C Norway
9 Leonardson et al. 2015 CONIFER S Sweden
10 Nes 2015 ABIBAL, BETULA, PICEA, PINSYL, SORBUS Quebec, CAN, S and C Norway
11 Nosko et al. 2020 ABIBAL Newfoundland, CAN
12 Siipilehto & Heikkilä 2005 PINSYL C Finland
13 Speed et al. 2013 BETULA, PICEA, PINSYL, POPTRE, SALIX, SORBUS S and C Norway
14 Thompson et al. 1992 ABIBAL, BETULA, POPTRE, PRUPEN Newfoundland, CAN
Table 2. Abbreviations of the tree species or genera used in the meta-analyses, assessing effect sizes of moose exclusion on seedling density and height, and sources (referring to Table 1) for analyses of density or height, respectively.
Abbreviation Tree species Density Height
1 ABIBAL Abies balsamea (L.) Mill. 5, 10, 14 5, 11, 14
2 BETULA Betula papyrifera Marshall 5, 10, 14 5, 14
3 BETULA Betula pendula Roth & B. pubescens Ehrh. 3, 8, 10, 13 3, 4
4 CONIFER coniferous seedlings 9
5 DECID deciduous seedlings 2
6 PICEA Picea abies (L.) H. Karst. 3, 8, 10, 13 3, 4
7 PICEA Picea glauca (Moench) Voss 5, 10 5
8 PICEA Picea mariana (Mill.) Britton, Sterns & Poggenb. 5
9 PINSYL Pinus sylvestris L. 3, 8, 10, 13 3, 4, 12
10 POPTRE Populus tremula L. 5, 13, 14 4, 14
11 PRUPEN Prunus pensylvanica L. f. 5, 14 14
12 QUERCUS Quercus robur L. & Q. petraea (Matt.) Liebl. 6 6
13 SALIX Salix alaxensis (Andersson) Coville 7
14 SALIX Salix brachycarpa Nutt. 7
15 SALIX Salix caprea L. 3, 13 1, 3
16 SALIX Salix lasiolepis Benth. 7
17 SALIX Salix novae-angliae Andersson 7
18 SORBUS Sorbus americana Marshall 10
19 SORBUS Sorbus aucuparia L. 3, 8, 10, 13 3
1

Fig. 1. Observed effect sizes for coniferous seedling or sapling density and height (treatment = moose exclosure) for individual tree species or genera (abbreviations explained in Table 2). Negative values indicate lower seedling densities and positive values higher seedling densities in the moose exclosure plots compared to the non-fenced control plots. Numbers of observations and heterogeneity test results are shown. The right y-axis depicts the weight of observational groups.

2

Fig. 2. Observed effect sizes for deciduous seedling or sapling density and height (treatment = moose exclosure) for individual tree species or genera (abbreviations explained in Table 2). Negative values indicate lower seedling densities and positive values higher seedling densities in the moose exclosure plots compared to the non-fenced control plots. Numbers of observations and heterogeneity test results are shown. The right y-axis depicts the weight of observational groups.

3

Fig. 3. Relationships between the proportion of deciduous seedlings or saplings (as percentage of the total number) and the effect size of moose exclusion for seedling or sapling (A) density and (B) height. Linear regressions are calculated separately for deciduous and coniferous seedlings. The zero line is indicated, and positive effects sizes indicate positive effects of moose exclusion.

4

Fig. 4. Relationships between the total stand density (as plants per ha) and the effect size of moose exclusion for seedling or sapling (A) density and (B) height. Linear regressions are calculated separately for deciduous and coniferous seedlings. The zero line is indicated, and positive effect sizes indicate positive effects of moose exclusion.

5

Fig. 5. Relationships between the observation time (years after moose exclusion) and the effect size of moose exclusion for seedling or sapling (A) density and (B) height. Linear regressions are calculated separately for deciduous and coniferous seedlings. The zero line is indicated, and positive effect sizes indicate positive effects of moose exclusion.

6

Fig. 6. Relationships between the estimated moose density and the effect size of moose exclusion for seedling or sapling (A) density and (B) height. Linear regressions are calculated separately for deciduous and coniferous seedlings. The zero line is indicated, and positive effect sizes indicate positive effects of moose exclusion.