New York Metropolitan Flora

Genus: Populus

Populus grandidentata
Populus grandidentata   Michx.  -  Big-toothed Aspen

Photo © by Brooklyn Botanic Garden

By Steven D. Glenn

Not peer reviewed

Last Modified 03/11/2013

Back to Salicaceae

Nomenclature

Populus L., Sp. Pl. 2: 1034. 1753. Gen. Pl., ed. 5, 456. 1754. LECTOTYPE: Populus alba L. designated by Britton & Brown (1913).

Tremula Dumort., Bijdr. Natuurk. Wetensch. 1: 46. 1826. TYPE: Tremula vulgaris Opiz (=Populus tremula L.).

Octima Raf., Alsogr. Amer. 42. 1838. TYPE: Octima canescens Raf. (Populus canescens (Aiton) Sm.).

Monilistus Raf., Alsogr. Amer. 42. 1838. TYPE: Monilistus monilifera Raf.

Aigeiros Tidestr., Elys. Marian., Ferns 2: 15. 1910. TYPE: Unknown.

Key to the species of Populus

1. Leaves white-tomentose beneath...2
1. Leaves glabrous or nearly so (densely white-tomentose on young leaves of P. balsamifera and P. grandidentata)...3

2. Leaves lobed; lower surface densely tomentose...Populus alba
2. Leaves entire or dentate; lower surface more sparsely tomentose...Populus ×canescens

3. Petioles terete...4
3. Petioles strongly laterally compressed...5

4. Leaf outline slightly convex toward the blunt or rounded tip; pedicels 2-8 mm long...Populus heterophylla
4. Leaf outline slightly concave toward the very acute to short acuminate tip; pedicels less than 2 mm long...Populus balsamifera

5. Leaves strongly deltoid or diamond-shaped; leaf margin with firm, colorless border thicker than the adjacent major veinlets; stamens more than 14; scales of aments glabrous, fringed with many thread-like segments...6
5. Leaves orbicular to reniform or obscurely deltoid; leaf margins often without colorless border; stamens less than 13; scales of aments pilose, fringes with only 3-7 linear or narrowly lanceolate segments...8

6. Glands prominent at junction of blade and petiole; leaf blade deltoid...7
6. Glands absent at junction of blade and petiole; leaf blade diamond-shaped...Populus nigra

7. Blades of early leaves light green above; leaf margins very coarsely dentate, the largest teeth 2-6 mm deep, ciliate...Populus deltoides
7. Blades of early leaves dark green above; leaf margins coarsely dentate, the largest teeth 1-2 mm deep, not ciliate...Populus ×jackii

8. Leaf margins closely crenate-serrate; buds and new growth glabrous...Populus tremuloides
8. Leaf margins closely undulate dentate; buds and new growth tomentose...Populus grandidentata

List of Populus Species

Populus alba Populus balsamifera Populus x canescens (P. alba × P. tremula) Populus deltoides Populus grandidentata Populus heterophylla Populus x jackii (P. balsamifera × P. deltoides) Populus nigra Populus tremuloides

References to Populus

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