Does it look like this?
Cascara
Rhamnus purshiana
I can't make out your leaves.
"Cascara-Rhamnus purshiana--Not edible. May cause stomach ache or diarrhea. Berries black, numerous. July-Aug. Tree with alternate glossy green leaves, strongly viened. Common in developed area, uncommon in woods. Commonhouse. The gray bark of this tree contains a powerful laxative, and the berries contain smaller amounts of this same property"
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And these are Elderberries