I've had a facebook reply from the guy who wrote a book on Bryce Higbee glass, and although that company made glass using the same wood pattern and colour, he says it's not one of theirs. There is no UV either. After drawing a blank in the USA I'm beginning to think it's a UK piece, not surprising really as it was found in the UK. So we're back to either Heppell, Greener, maybe Burtles Tate or another.