Awful thorny bushes w/ no berries

[Midnight Rambler]

You said the leaves were heart-shaped; do they have the narrow end at the stem, and the broad (indented) end at the tip? If so that's definitely Himalayan raspberry, there's almost nothing else that looks like that. Most other plants, including other raspberries, have leaves that are broader at the base or are oval if they're wider toward the tip.

They can get very tall; instead of being brambly like other raspberries the canes first grow straight up to get above the tree fern canopy, then arch over. Unfortunately that means they do very well even in closed forest that other raspberry species can't handle.