Megan Hall: Welcome to Possibly, where we take on huge problems like the future of our planet and break them down into small questions with unexpected answers. I’m Megan Hall. 

This episode, we’re going to take a crack at nuts. You might’ve seen ads for healthy almonds, packs of pistachios, and more. They seem to be the “it” snack these days. So we wondered, what’s the impact of all those nuts? 

We had Max Kozlov and Fatima Husain from our Possibly Team look into this. Welcome, Max and Fatima!

Max Kozlov: Hi, Megan! 

Fatima Husain: Hello! 

Megan Hall: So, why are we talking about nuts? 

Max Kozlov: Well, nuts have become incredibly popular these days. 

Megan Hall: Really? Haven’t people always eaten nuts?

Fatima Husain: Yes, but the demand for tree nuts like almonds, pistachios, and walnuts has gone way up. Americans eat about 6 times as many almonds and more than 11 times as many pistachios as they did half-a-century ago!

Megan Hall: Is that a problem? 

Max Kozlov: Well, tree nuts are lucrative for growers, but they need a lot of water. It can take more than a gallon of water to grow just ONE almond or pistachio. 

Megan Hall: So, how much water does the nut industry use up? 

Fatima Husain: To find out, we called David Goldhamer, a water management specialist at University of California, Davis.

Max Kozlov: He says eighty percent of the world’s almonds are grown in the central valley of California, which is a pretty dry place with frequent droughts, so farmers can’t count on rain to help water the trees. 

David Goldhammer: How that relates to water resources in this state, has not been written about or discussed or is even apparent to most people.

Max Kozlov: He says the exported almond industry alone uses 1.9 trillion gallons of water each year. 

Megan : can you help me picture how much that is?

He says to try to imagine those big trucks that deliver gas to gas stations. 

David: If you put that amount of water in the trucks and put those trucks nose to tail at the equator it would go around the earth something like 28 times.

Megan Hall: Does this mean I should stop eating almonds?

Fatima Husain: Not necessarily. Let’s put this in perspective. Nuts are a good source of protein if you’re trying to avoid meat or cow milk.

Max Kozlov: And while nut production uses a lot of water, it’s still less than some other common protein sources.

Fatima Husain: For example, pound for pound, almonds use about four times less water than beef.  

Max Kozlov: And a pound of almonds has more calories than a pound of beef, so almonds use even less water per calorie.  

Megan Hall: But it still seems like we should find a way to grow these nuts without so much water. 

Max Kozlov: That’s not easy — trees need water! But David is actually working on this problem, using a technique called “deficit irrigation.”

Fatima Husain: That’s when growers deliberately cut back on water, trying to get the best harvest with the least amount of moisture.

Max Kozlov: He’s found that this technique can safely reduce water use in almond trees by up to 10 percent. The problem is, there’s not a real incentive for growers to make even this small change.

Fatima Husain: So for now, growing almonds and other tree nuts will continue to require a lot of water. 

Max Kozlov: But, if water use is important to you, consider cutting back on beef or dairy milk first.

Fatima Husain: for a less water hungry snack, try switching to ground nuts like peanuts. They use less water than tree nuts, and are typically grown in wetter places, so they need less irrigation. 

Megan Hall: Great! Thanks, Max and Fatima! 

That’s it for today. For more information, or to ask a question about the way you recycle, use energy, or make any other choice that affects the planet, go to the public’s radio dot org slash possibly. Or subscribe to us wherever you get your podcasts. 

Possibly is a co-production of the Institute at Brown for Environment and Society and the Public’s Radio. 

The post Nuts for sustainability appeared first on TPR: The Public's Radio.