I use and recognise both. I think I agree with Mav that there is some sort of relation to scale - if boundary is clearly visible, it's singular, if it stretches away, it's not.

More or less, anyway. When I was a kid, there was a small wood on the other side of the railway track called 'Sooty Woods'. I see nothing wrong with that sentence!!!! And Birnham Wood is singular despite being bigger (or so I assume) than my nostalgic little home patch.

What do you US'ns make of 'can't see the wood for the trees', then? In Bringlish (can I call it that?), it clearly means 'can't see the overall picture for the detail'. Do you say 'can't see the woods for the trees' or what?!?

...and as for the Australians calling it bush when their trees are higher than the ones I grew up with...