In article , "Harvey"
writes:

This is a thorny, wirey vine seen extensively in Virginia & West Virginia at
least. Usually under trees, climbing but fairly low & never as dense as
those pictures. But the leaves are Saggitate to Hastate/spear shaped,
margin I think entire, rather dull almost yellowish green.
That does not agree with the pictures of Kudzu!
Never seen a flower on it.

So what was it?? Maybe it is a native!

Harvey


That sounds like Greenbrier or Smilax.
Probably S. rotundifolia.
The flowers are very small, in umbels, greenish colored.
Berries are dark blue-black.
In California we have S californica.
It's in the Lily Family.

Emilie
NorCal