You can take the girl out of the woods, but you can’t take the woods out of the girl — unless, of course, you take the woods away altogether. Such are the tough lessons learned in “Toorbos,” a satisfying marriage of folky period romance and environmental parable from the misty, mossy depths of South Africa’s Knysna forest region: a national beauty spot much enshrined in local literature and lore, but rarely given this kind of grand-scale screen showcase. René van Rooyen’s handsome Afrikaans-language drama is adapted from the last in a celebrated quartet of “Forest Novels” by the late Dalene Matthee, an author whose renown abroad has never quite matched her national-treasure status at home — but is this arthouse fare as internationally accessible as it is locally evocative, unsurprisingly selected as this year’s official South African Oscar submission.