Type of berry found in China?

Question

A Chinese friend described a berry which is long and slender, black in color and has the same bumpty texture as raspberries/blackberries. She was surprised to see one in the U.S. Berries not available to purchase. She said she thought we have the trees but don't eat the berries.

Answer 1

Sounds like she was talking about a Mulberry.  Mulberries are common in the wild here on the East Coast and a delight to eat off the tree on some late spring walk.