vert foret, vert fonce -- same colour?

No, Vert Foret is the Pine Green, whereas Vert Fonce is the Olive Green.
http://forum.purseblog.com/balenciaga-color-reference/green-color-family-pics-only-140427-3.html

Check out the beautiful bags of two tPFers: post 32 for Vert Fonce and post 35 for Vert Foret.

Beautiful bags! Thanks for the clarification.

The two colours didn't look the same to me but I got confused because they are both 2007 colours. Vert foret is F/W 2007, was vert fonce S/S 2007?

I'm looking forward to seeing some images of the 2008 vert thyme.
 
^^No, they're both f/w 07. Most people call the vert foret 'pine' I think - probably helps with the confusion. Plus its very descriptive of the actual colour - vert fonce is more of a green/brown colour.