Tree species | Year of planting | Plant spacing (m) | Diameter1 mean ± s.e. (cm) |
---|---|---|---|
Littleleaf linden (Tilia cordata) | 1972 | 4 × 4 | 8.3 ± 0.4 |
White birch (Betula papyrifera) | 1966 | 2 × 2 | 9.3 ± 1.2 |
Norway maple (Acer platanoides) | 1970 | 4 × 4 | 9.1 ± 0.2 |
Honeylocust (Gledltsia tri-acanthos var. inermls | 1970 | 4 × 4 | 13.5 ± 0.5 |
Pin oak (Quercus palustris) | 1969 | 4 × 4 | 13.7 ± 0.5 |
Sycamore (Platanus occidentalis) | 1962 | 2 × 2 | 14.6 ± 0.9 |
English elm (Ulmus procera) | 1968 | 2 × 2 | 15.2 ± 0.8 |
Hackberry (Celtis occidentalis) | 1962 | 2 × 2 | 16.0 ± 0.9 |
Green ash (Fraxinus Pennsylvania var. lanceolate) | 1960 | 2 × 2 | 18.9 ± 1.2 |
Tulip tree (Liriodendron tulìpifera) | 1970 | 4 × 4 | 19.0 ± 0.6 |
↵1 Diameter at a marked height approximately 1 m above the ground