Means and standard deviations for shoot length, HWA egg sacs, percentage of new growth, and mite damage on matched populations of Tsuga chinensis and T. canadensis growing at the Arnold Arboretum.
| Species | No. seedlings sampled | Mean plant height (cm) | Exposure | Mean shoot length (cm)* | Mean no. HWA egg sacs per shoot | Mean % shoots w/new growth | Mean % shoots w/mite damage | ||
|---|---|---|---|---|---|---|---|---|---|
| Sun | Gap | Shade | |||||||
| Tsuga chinensis | 38 | 169.0 ± 38.0 (range = 84 to 240 cm) | 8 | 18 | 12 | 10.3 ± 3.5 (range = 5.5 to 17.2) | 0 | 100 | 8.7 ± 24.7 (range = 0 to 92) |
| Tsuga canadensis | 33 | 182.6 ± 94.5 (range = 45 to 380 cm) | 2 | —— | 31 | 4.9 ± 1.2 (range = 2.7 to 8) | 3.8 ± 4 (range = 0 to 14.7) | 45.4 ± 38.8 (range = 0 to 100) | 20.9 ± 27.6 (range = 0 to 100) |
↵* Based on samples of 12 shoots per tree.