I think you should reread Tolkien as well. He might not spend much time on human structures, but he goes overboard on lavish descriptions of random bits of wilderness. That is, after all, part of his theme: the victory of the natural over the manmade.
The victory of British pastoralism over military industrialism more like.
Since there's some difference of opinion on this, here's a random excerpt so we can see what Tolkien's actually doing and how he does it:
Suddenly Frodo himself felt sleep overwhelming him. His head swam. There now seemed hardly a sound in the air. The flies had stopped buzzing. Only a gentle noise on the edge of hearing, a soft fluttering as of a song half-whispered, seemed to stir in the boughs above. he lifted his eyes and saw leaning over him a huge willow-tree, old and hoary. Enormous it looked, its sprawling branches going up like reaching arms with many long-fingered hands, its knotted and twisted trunk gaping in wide fissures that creaked faintly as the boughs moved. The leaves fluttering against the bright sky dazzled him, and he topped over, lying where he fell upon the grass.
(The Fellowship of the Ring, Bk1, Ch6, The Old Forest)
There's a lot of description here and I believe that it's doing two things: 1) setting mood (the scene is just prior to meeting Tom Bombadil, and the aged willow motif presages that meeting); 2) setting up action. The willow is malign and in the subsequent passage almost kills several of Frodo's band.
I think this shows that making description relevant to action and mood doesn't mean that you must write less of it (Tolkien is indeed a prolix describer -- and has set the stamp on epic fantasists ever since); it also shows that setting descriptions fit better in the story if they're
relevant and not simply
lovingly detailed.
Tolkien's novel is wordy principally because he moves his characters around a lot, but at least whenever he does
something happens. We can argue about whether all the somethings are equally interesting and integral to the plot (Bombadil is largely irrelevant, for example) but what we can't argue is that Tolkien's descriptions are flapping loose from the drama.
Lord of the Rings had competent and devoted editing, which is more than can be said for many modern fantasy epics.
Self-editorial discipline is almost unknown among amateur fantasists, and patchy even among the pros. Evidence of editorial discipline is not so much the length of the books (fantasy readers love door-stops and so be it) but
integration and
parsimony in the text, and
impact in the drama.