Well, in case you did, here's the answer. At least, this is what it looked like last month in Gansu province, a very poor western part of the country that also contains some very beautiful scenery.


In less scenic parts of Gansu, including near the capital of Lanzhou, hillsides were long ago stripped of trees and shrubs so they could be turned into little terraced farming plots or grazing areas for sheep. Many then eroded and turned into pure wasteland. That's where the trees are going back in.


It appears to work this way: local farmers are paid to girdle the hillsides with row after row of little foot-wide terraces. They plant trees on each terrace. Somehow they must get water to the trees (it's a dry region). On a few hillsides, we saw thickets of saplings 8 or 10 feet tall, which looked like they would survive. Most hillsides look like the ones below (and after the jump).


Now you know.


(Scale note: the baby trees in this first shot are about three feet tall; they're shown on a very small hill.)


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