Article Figures & Data
Tables
- Table 1.
Numbers and percentages of trees affected by various factors on the Virginia Tech campus.
Abiotic Biotic Total no. trees % paved area beneath crown Ice damage Lightning Heart rot Chlorosis Dutch elm diseasez Other diseasesy Acer nigrum 20 9 (45%) 7 (35%) 3 (15%) 2 (10%) Chamaecypańs pisifera 24 4 (17%) Cornus florida 31 4 (13%) 2 (6%) 1 (3%) 1 (3%) 2 (6%) Ulmus americana 13 8 (62%) 5 (38%) 9 (69%) Quercus alba 27 4 (15%) 5 (18%) 1 (4%) 1 (4%) Platanus occidentalis 12 6 (50%) 3 (25%) 2 (17%) Acer saccharum 25 16 (64%) 9 (36%) 14 (56%) Quercus palustris 19 15 (79%) 1 (5%) 14 (74%) Quercus rubra 29 23 (70%) 2 (7%) 1 (3%) 2 (7%) 2 (7%) 2 (7%) Totals (% of total trees) 200 85 (43%) 37 (18%) 3 (1.5%) 20 (10%) 17 (8.5%) 9 (4.5%) - Table 2.
Annual diameter growth of trunk and crown, 1993 to 1995 (means and their standard errors).
Trunk Crown N Growth (mm) s.e. Growth (m) s.e. Chamaecyparis pisifera 2.8 1.18 24 Cornus florida 3.6 0.56 0.11 0.087 31 Acer nigrum 3.8 0.84 –0.48 0.203 20 Ulmus americana 7.6 1.92 –0.52 0.273 13 Quercus alba 9.9 2.58 –0.19 0.254 27 Acer saccharum 10.2 2.89 0.33 0.138 25 Platanus occidentalis 10.5 2.10 0.43 0.111 12 Quercus palustris 11.8 1.49 0.016 0.118 19 Quercus rubra 13.4 2.20 0.51 0.094 29 - Table 3.
Contrasts between pairs of species, by 1-factor ANOVA, in diameter growth of trunk and crown. (Means followed by the same letter are not significantly different at P ≤ 0.0001.z)
Trunk growth (mm) Chamaecyparis pisifera Cornus florida Acer nigrum Quercus rubra 2.8 a 3.6 a 3.8 a 13.4 b Crown growth (m) Ulmus americana Acer nigrum Quercus alba Acer saccharum Platanus occidentalis Quercus rubra –0.52 a –0.48 a –0.19 a 0.3 b 0.43 b 0.51 c ↵z These were the only significant differences between pairs of species.
- Table 4.
Numbers of trees in each stress group classified by paved area beneath the crown.
Species ≤ 10% of paved area > 10% of paved area N Acer nigrum 9 11 20 Cornus florida 4 27 31 Ulmus americana 7 6 13 Quercus palustris 15 4 19 Quercus rubra 23 6 29 Acer saccharum 16 9 25 Platanus occidentalis 5 6 12 Quercus alba 23 4 27