Table 6 Absolute and relative frequency (in brackets) of the different TreM and tree vigor classes by species, and p-values of the pairwise comparisons for categorical data. Bold p-values indicate significant results at p < 0.05. a: Dead trees of unidentified species were not considered for the pairwise comparison of tree species within each TreM category
Category | Class | Frequency (n) | Pairwise test of independence between tree species (adjusted p-value) | |||||
|---|---|---|---|---|---|---|---|---|
Sugar maple (SM) | American beech (AB) | Other species (Osp) | Unknown species | SM–AB | SM–Osp | AB–Osp | ||
TreM presence | Presence | 176 (72%) | 56 (23%) | 12 (5%) | – | 0.094 | 1 | 0.738 |
Absence | 172 (80%) | 32 (15%) | 12 (6%) | – | ||||
TreM class | Bark loss | 47 (77%) | 10 (16%) | 4 (7%) | – | 0.003 | 1 | 0.201 |
Broken branch or top | 25 (83%) | 2 (7%) | 3 (10%) | – | ||||
Crack | 6 (86%) | 0 (0%) | 1 (14%) | – | ||||
Crown deadwood | 14 (56%) | 10 (40%) | 1 (4%) | – | ||||
Fungi | 4 (44%) | 5 (56%) | 0 (0%) | – | ||||
Trunk base rot hole | 8 (100%) | 0 (0%) | 0 (0%) | – | ||||
Trunk rot hole | 46 (88%) | 3 (6%) | 3 (6%) | – | ||||
Woodpecker lodge | 22 (92%) | 2 (8%) | 0 (0%) | – | ||||
Tree vigor | Vigorous | 257 (83%) | 34 (11%) | 18 (6%) | – | < 0.001 | 1 | 0.001 |
Senescent | 12 (21%) | 42 (75%) | 2 (4%) | – | ||||
Deada | 58 (45%) | 34 (26%) | 5 (4%) | 32 (25%) | ||||