"Ki Do (The Way of the Trees)" by Sarah Thomas
I really enjoyed the story this week in Strange Horizons--I think I'd have liked the form regardless, as it involves (minimalist) poetry and crafting something beautiful over many years. But that it's about trees bumps it up even higher for me (have I mentioned my obsession with trees? Oh yeah, once or twice, I suppose...).
While you're there, check the two-part story that ran the last two weeks: Will McIntosh's "Linkworlds." It's not as much up my alley as this week's, but I quite enjoyed it nonetheless. It's space fiction in a universe that's nothing like ours.