The plowman homeward plods his weary way, And leaves the world to darkness and to me. (3-4)
The relationship of man and the natural world is brought up in the first stanza. The speaker watches a farmer go wearily home from the fields. That right there is one way to have a relationship with the natural world—work on a farm! You'll be in close touch with the earth, all right. But the speaker has a different type of relationship with the earth. He's pleased to be left alone, in the dark, with the natural world around him.
And all the air a solemn stillness holds, Save where the beetle wheels his droning flight, (6-7)
All the repeated S and Z sounds in these lines mimic the "buzzzzzzzzz" sound of the beetle "droning" along. The speaker sure has a good ear for nature.
Beneath those rugged elms, that yew-tree's shade, Where heaves the turf in many a mould'ring heap, Each in his narrow cell for ever laid, The rude forefathers of the hamlet sleep. (13-16)
It seems important to the speaker that the dead villagers are resting in a very natural setting—they're under elms and yew trees, under piles of turf. They're not in some musty churchyard or buried under stone monuments; they're one with nature. This seems to be the ideal way to spend eternity, at least from the speaker's point of view.
How jocund did they drive their team afield! How bow'd the woods beneath their sturdy stroke! (27-28)
The speaker imagines how the villagers worked in the natural setting of their farms and village. They were cheerful and strong! And the wood that they chopped for fuel or for building supplies seemed to acknowledge the superior strength of the villagers: it "bow'd" before them.
"There at the foot of yonder nodding beech That wreathes its old fantastic roots so high, His listless length at noontide would he stretch, And pore upon the brook that babbles by. (101-104)
Toward the end of the poem, we get to hear more about the speaker's relationship with nature. He wants to be remembered as the kind of guy who used to stretch out lazily under a tree and listen to the babbling brook nearby. Why might he want to be remembered this way? The villagers' relationship with the natural world always seems to have to do with work—they plow the fields and work with their livestock and chop wood for fuel. The speaker, meanwhile, gets to nap under a tree. What's up with that? Does the poem seem to privilege one kind of relationship with nature over the other?