Notice the reddish tint in the lateral stems. It's more pronounced now than it has been all winter.
This is either a wild rose or blackberry out on the edge of a wood in between vineyard parcels. I think that its thorns are amazing looking. Today will be our last "warm" day before a weather system moves in, bringing temperatures back down for the weekend. I hope we don't get a freeze, but that is certainly a possibility this time of year.