SCOTT SIMON, HOST:
You see a lot of electric cars and solar panels in California. They're the most visible signs of the state's ambitious climate change policies. But now California is setting its sights on a lower tech way to try to cut carbon emissions as well, and that's soil. Here's more from Lauren Sommer of member station KQED and NPR's energy and environment team.
LAUREN SOMMER, BYLINE: Most farmers do not get along with weeds. In California's Central Valley, they spend a lot of time getting rid of them...
JOSE ROBLES: You see a lot of orchards that don't have any weeds. Everybody wants to have the orchards nice and clean.
SOMMER: ...But not Jose Robles. When I visited his almond orchard a few months ago, the ground under his trees was a carpet of green, full of mustard plant and clover.
ROBLES: This will grow.
SOMMER: Oh, it'll be high.
ROBLES: Yes. It'll grow two, three feet high.
SOMMER: Robles planted these weeds on purpose, which technically doesn't make them weeds anymore. They're a cover crop. His neighbors really don't get it.
ROBLES: I've heard them said, oh, we're in the business of growing almonds, not in the business of growing weeds (laughter).
SOMMER: He got the idea a few years ago during California's severe drought when his soil was drying out too fast. He knew that a richer soil holds moisture better, but there wasn't a lot of organic matter in his orchard to build it up and make it that way.
ROBLES: We spray and kill the weeds, and we were killing everything.
SOMMER: So he decided to feed his soil. He'll mow these weeds and let them decompose, along with some extra compost and mulch. He's already seen a difference.
ROBLES: The trees - they don't stress as much because they hold the moisture a lot longer.
SOMMER: It's more work for him, but he got a grant from California to help cover his costs, a grant that's from the state's climate change program. Now, Robles wasn't looking to get involved with climate change.
ROBLES: No. We just started because of the water.
SOMMER: But soil and plants are a key part of the state's climate change strategy because they could absorb as much as 20% of California's emissions.
KATE SCOW: Soil is alive. There's farmers that know that.
SOMMER: Kate Scow is a professor of soil microbial ecology at the University of California, Davis. We're standing in a large wheat field near campus where she starts digging in the dirt.
SCOW: Wow, OK.
SOMMER: She's really into soil.
SCOW: Well, that's my weirdo thing.
(LAUGHTER)
SCOW: All right. See; we're starting to hit the mineral soil.
SOMMER: This is where the carbon is stored, she says. Plants soak up the carbon dioxide from the air. When a plant dies, its roots and leaves get broken down by microbes and fungi. That's how the carbon from the air gets into the soil.
SCOW: And the deeper you can get it in the soil, like, especially below the plow layer, the more stable and secure it's going to be.
SOMMER: That's important to lock the carbon up, which is what California wants. The state has a goal to become carbon neutral by 2045.
JEANNE MERRILL: We have very ambitious climate goals and without natural and working lands, California simply won't get there.
SOMMER: Jeanne Merrill is with the California Climate and Agriculture Network, a coalition of ag groups. She says farmers should be part of California's climate effort because they're already facing its impacts, like more extreme weather.
MERRILL: Some are willing to say that it's climate change. Others are unsure. But I think many know that things have - are changing, and they need different tools.
SOMMER: Merrill says farmers are interested in the climate programs if only because it can help them cope with extended droughts. Hundreds have signed up, but state climate officials say the soil program needs to be five times larger to have a real impact. And that will be up to state lawmakers as they sort out California's budget in the coming weeks. For NPR News, I'm Lauren Sommer. Transcript provided by NPR, Copyright NPR.
