Easily-confused!
If your specimen is a:and has stem­/­leaf ar­range­ment:and the leaves have:and the bark is/has:and the twigs:and the fruit (if present):then you have:
tree╫ opposite (most species) ___ smooth,
taper at both ends, and
pass the dogwood leaf test
no con­spic­u­ous lenticels nor strong colors lookalike dogwood genus Cornus
sub-opposite small ▲▲ teeth dark, lots of light-colored lenticels ;
inner bark=­or­ange (scrape with knife)
often have a terminal thorn are small, black, taste dis­gust­ing after a few seconds—spit it out lookalike common buckthorn Rhamnus cathartica
╟ alternate ___ smooth or
very small ▲▲ teeth (use 🔎︎ hand-lens)
dark, lots of light-colored lenticels no terminal thorn ;
hairy
lookalike glossy buckthorn Frangula alnus
no more than waist-high (<1 m) (<3 ft) ▲▲ teeth no hair lookalike alderleaf buckthorn Rhamnus alnifolia
tree ▲▲ teeth, visible within arm's length dark, lots of light-colored lenticels ;
if mature, looks covered with burnt potato chips­/­crisps
are small, black, taste like 🍒︎ cherry even if sour this plant, please continue below . . .

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Learn more about 🍒︎ black cherry Prunus serotina

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