Least squares (LS) means (standard error) of the percent increase in area of discoloration (Area) associated with lag installation classified by (a) years that lags remained in trees prior to harvest, (b) species [sugar maple (AS), paper birch (BP)], and (c) shank diameter (mm). Species and shank diameter were nested within year.
| (a) | (b) | (c) | ||||||
|---|---|---|---|---|---|---|---|---|
| Yearsz | n | Areay | Speciesx | n | Area | Shank Diameterx | n | Area |
| 1 | 16 | 192 (30.3)ab | AS | 10 | 158 (33.9)a | 6.4 | 4 | 246 (52.0)a |
| BP | 6 | 226 (45.5)a | 9.5 | 12 | 139 (29.4)a | |||
| 2 | 33 | 115 (17.5)b | AS | 16 | 97.9 (25.6)a | 6.4 | 16 | 100 (25.6)a |
| BP | 17 | 133 (25.0)a | 9.5 | 17 | 130 (25.0)a | |||
| 3 | 18 | 213 (28.5)a | AS | 0 | n/aw | 6.4 | 14 | 240 (26.9)a |
| BP | 18 | 213 (28.5) | 9.5 | 4 | 186 (50.3)a | |||
| 4 | 10 | 422 (61.6)c | AS | 8 | 224 (53.8)a | 6.4 | 1 | n/aw |
| BP | 2 | 620 (89.2)b | 9.5 | 9 | 420 (40.3) | |||
↵zFor each year, LS means followed by the same letter were for not significantly different (P > 0.05) by Tukey’s HSD test.
↵yArea was calculated as percent increase from the hole drilled to insert the lag: (area of discoloration – area of drilled hole) / area of drilled hole.
↵xLS means for each level of species and shank diameter within each year followed by the same letter were for not significantly different (P > 0.05) by Tukey’s HSD test.
↵wn/a indicates that insufficient measurements were made for valid comparison.