with petiole = short (≤½ as long as leaf), blade=narrow or soft texture, veinlets=not meshed

OR it does NOT (meaning the petiole=long [>½ as long as leaf], blade=wide and firm texture, veinlets=meshed), and …

petiole=— flat, and …
blade base=___ flat, teeth=very small (>5/cm) (>12/in), tree very tall thin
European black poplar  Populus nigra

blade base=___ flat, teeth=medium (2-3/cm) (5-8/in)
eastern cottonwood  Populus deltoides

blade base= rounded (U-shaped), teeth=few+large, leaf longer than wide
big-toothed aspen  Populus grandidentata

blade base= rounded (U-shaped), teeth=small, leaf about as long as wide
quaking aspen  Populus tremuloides

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plant terminology