Black-poplar
Scientific name: Populus nigra L.
Diagnostic features
Trees of various habit, not suckering.
Leaves rhombic-ovate to trullate, broadly cuneate (to truncate) at base, without glands, serrate with many small teeth.
This species is keyed out on Page 1678: Black-poplars in the Text Key.
Key to the subspecies and cultivars of Populus nigra:
1a. Tree with spreading crown; trunk with large burrs.
............................. Populus nigra betulifolia
1b. Tree fastigiate, with ± erect branches; trunk without burrs.
............................................................ 2.
2a. Young leaves and stems sparsely pubescent; male.
............................ Populus nigra-'Plantierensis'
2b. Young leaves and stems glabrous.
............................................................ 3.
3a. Tree very narrowly fastigiate; male.
.............................. Populus nigra-'Italica'
3b. Tree often more widely fastigiate; female.
............................. Populus nigra-'Gigantea'
Hybrids
- Populus nigra x Populus jackii(x). In Leeds, Midwest Yorks, Populus jackii(x) has been pollinated by Populus nigra to give strongly regenerating hybrids on waste ground, first found 1983. The hybrids show variable characters of the parents on 1 plant: c.1/2 of the petioles are glabrous, 1/2 pubescent; c.1/2 the leaf-margins are serrate, 1/2 crenate; leaf-base is cuneate (as in Populus nigra) in most cases but c.20% are rounded (shape not in either parent); leaf lowerside colour varies between those of the parents. This is effectively Populus balsamifera x Populus deltoides x Populus nigra.
- See also Populus canadensis(x) Moench (= Populus nigra x Populus deltoides Marshall)
- See Populus berolinensis(x) (K. Koch) Dippel (= Populus nigra-'Italica' x Populus laurifolia Ledeb.) |
