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, teeth=few+large, leaf longer than wide   >   big-toothed aspen Populus grandidentata
blade base=∪ rounded, teeth=small, leaf about as long as wide   >   quaking aspen Populus tremuloides

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plant terminology