Perennial grains could be a key weapon against climate change. But not quite yet.

As climate change climbs the chart of existential threats, soil is getting a lot of attention. Back when it supported forest or grassland, before we cleared it to grow crops, it stored an awful lot of carbon.

By farming the land, we released the carbon. Now, there’s a major push to figure out how to put at least some of it back. The Land Institute, in Salina, Kansas, is on it, and I visited them last fall. “We lost about half the carbon in the first few decades after putting crops on prairie,” said Land Institute President Fred Iutzi, who was showing me around. “In some places it leveled off at about half of what was there pre-settlement, on some places it went down to about a third.”