As citrus greening destroys Florida’s citrus industry, one company thinks it may have found a solution. It starts in the ground.

Ted Geltz has learned a hard lesson about land in Florida. It’s only good for two things: citrus and real estate.

“If you can’t make it in citrus, then you sell it for houses,” Geltz, the business development director for Locus Agricultural Solutions, told NationSwell.

Geltz, who has been in the citrus industry for more than four decades, has watched as acres of orange trees become apartment complexes, storefronts and suburban mansions. Florida’s citrus production has declined 70% since 2005 due largely to an incurable citrus disease, but Florida’s land value has remained strong. It’s a circumstance that’s pushed thousands of citrus growers to sell their land.

For the few growers that remain, Geltz knows that their value isn’t just the land itself— it’s the soil.

Without the right soil, a citrus tree won’t have the nutrients it needs to stay healthy and produce juicy fruit. But healthy trees do more than just grow delicious food. They absorb carbon from the atmosphere and that carbon eventually cycles back into the soil, creating a carbon sink.

The planet’s soil has already stored an estimated 2,500 gigatons of carbon — four times more than the amount stored in all plants and animals and three times the amount currently in the atmosphere. By cultivating healthy soil, researchers believe there’s potential to store much more.

It isn’t just dirt that stores carbon — it’s the millions of microbes living in the soil. “In a handful of soil, you’ll find tens of thousands of different types of bacteria, fungi, archaea, viruses and a whole soil food web,” Matthew Wallenstein, a professor of soil microbial ecology at Colorado State University, told NationSwell.

When plants photosynthesize, they take in carbon. That carbon is used to help grow every part of a plant, from its roots to its stems and leaves. Excess carbon is released as carbon-rich compounds through the root system, and when a plant dies, the microbes take in additional carbon from the dead plant material.

However, a long history of poor land management has created microbe-lacking soils and erosion. Many farm practices disrupt topsoil, where wind and water can sweep it away and release stored carbon. Since humans first began farming, there has been an estimated 133 gigatons of carbon released from the soil.

“The fact that we’ve lost a lot of carbon suggests that there’s a really big capacity to restore those soils,” Wallenstein said.

One way to mitigate climate change is to stop soil erosion and focus on restoration. Around the world, people are approaching ways to sequester carbon in soil from all angles.

A common strategy being used to restore soil and stop its erosion is regenerative agriculture. Practices like rotating which crops are grown, using compost or cover crops help rebuild the soil’s biodiversity and allow it to store larger amounts of carbon.

“There’s no silver bullet. It’s going to take a lot of different approaches, but soils offer one of the most scalable, practical, economical solutions today,” Wallenstein said.

The startup Locus Agricultural Solutions believes it has one solution to help mitigate climate change and increase farmers’ yields. Locus Agricultural Solutions developed a combination of bacteria and fungi called Rhizolizer. When added to crops, it targets roots and root growth. This allows the plant to take in more nutrients, grow stronger and produce higher yields.

“If the roots are healthy, the plant is healthy,” Karthik Karathur, the president of Locus Agricultural Solutions, told NationSwell. “It’s just like our gut, if we have a healthy gut, you predominantly are going to be healthy.”

The bacteria and fungi in Rhizolizer are traditionally found in soil. “It’s just that with industrial farming and the fact that we have done so much to the soil, the soils are not that healthy anymore,” Karathur said. While regenerative farming practices can help restore the soil, Rhizolizer accelerates this process, he said.

Locus Agricultural Solutions isn’t the first company to develop microbial additives, but it is the first to ferment the product in highly concentrated small batches and ship it in a refrigerated system.

That approach has led to hopeful results. An acre with Rhizolizer sequesters 8.6 more tons of carbon each year than an acre without. With 40,000 acres across the U.S. using the technology, it’s the equivalent of taking 47,000 cars off the road.

But the startup’s initial goal wasn’t to combat climate change. It was to help citrus growers in Florida.

In Florida, the citrus belt has long been known as the country’s provider of the tangy fruits. The Valencia oranges used for juice, the navels found in school lunches and the grapefruits for breakfast all likely originated in Central Florida.

In the 1970s, often referred to as the heyday of citrus, 941,000 acres of Florida were dedicated to producing 200 million boxes of fruit. Florida had well earned its title as a worldwide leader in citrus.

Then disaster hit. There were the freezes in 1983, 1985 and 1989, which damage the cold-intolerant trees. Citrus canker, a bacterial disease, infected the groves, and citrus blight followed soon after. Hurricanes struck.

But perhaps the worst challenge has been citrus greening.

In 2005, Florida saw its first symptoms of citrus greening, also known as huanglongbing or HLB. The disease attacks the tree’s vascular tissue, impairing its ability to take in nutrients. The trees weaken, growth slows and the fruits that develop never ripen. Today, citrus greening is present across the entire state — leading to a 21% decrease in the fresh fruit market and a 72% decrease in the production of fruits used for juicing.

“In a period of about five years, it just devastated the industry,” said Geltz. “And a lot of people just threw their hands up and said I’m done.”

The growers that didn’t leave have tried everything to cure greening.

Chris Troesch, a grower at Simpson Fruit Company, first tried targeting the psyllids, the insects infecting the citrus trees. But that didn’t work.

Then helicopters sprayed insecticide at night. No luck.

Troesch applied other microbial additives to the trees, which ended up being “snake oil.” Microbial products have a historically bad reputation because they’re often transported thousands of miles. By the time they reach the farmer, they’re no longer fresh and no longer have the positive results.

At one point, he was spending $2,500 to $3,000 per acre to keep the trees alive and productive, while the industry standard was closer to $850. It wasn’t a sustainable business model.

“Our standard as Florida, we’re supposed to be number one on taste, and we lost it all,” he told NationSwell.

Geltz convinced Troesch to give Rhizolizer a shot. He added it to his irrigation system and it helped. Troesch has used the product for two years and production is up 25%.

Rhizolizer isn’t curing the trees of citrus greening, but it does have a positive effect. “It’s not that we’re eliminating the disease,” Teresa DeJohn, the director of marketing for Locus Agricultural Solutions, told NationSwell. “It’s that we’re able to keep the roots healthy and improve root growth, which is very rare with that disease.”

The result? Higher yields and hope that citrus still has a future in Florida.

Kris Sutton, a farmer at Faryna Grove Care and Harvesting, faced a similar reality two years ago.

Born and raised in Florida, he started working at Faryna in 2005. Between 2008 and 2009, citrus greening hit his 850 acres.

The trees shrunk in size, and the little fruit that the tree produced wasn’t edible.

He, too, tried countless solutions with no success. Geltz persuaded him to try Rhizolizer instead, and it worked.

“The last two years have been the first time I’ve seen the production go up,” the 41-year-old said.

Sitting behind the once unproductive grove in Umatilla, Florida, is a trailer park. Sutton thinks about what the grove could’ve been if Rhizolizer hadn’t helped. “It’d be motor homes.”

With healthier and more productive trees, Sutton said he doesn’t plan on stopping anytime soon. He hopes the land stays in the family, and with a tractor-loving 6-year-old, there’s a good chance it will.

Fifteen percent of Florida’s remaining citrus acreage is using Rhizolizer. The citrus community is tight-knit and word travels fast, which has helped focus Agricultural Solutions.

Tim Whitaker, a grower at May Brothers Citrus, watched neighboring groves grow and strengthen. “Well, what are they doing? What’s making the difference?” he asked.

It was Rhizolizer. Over lunch, Whitaker pulls out his phone to show pictures of a healthy, productive tree completely covered with healthy Hamlin oranges.

“The tree can’t hold much more fruit than that,” he said. “But just a few years ago, you could count the number of fruit on a tree with two hands.”

Outside of Florida, Locus Agricultural Solutions is working with farmers who grow everything from cantaloupes, to potatoes, to apples and strawberries.

Depending on the location and crop, farmers have seen a yield increase between 5% and 45%, said Karathur.

Since Rhizolizer is fermented in small batches, the goal is to have a microbrewery in every farming community.

Those breweries, Karathur believes, will support rural communities, restore land and build a future for the planet.

“Human beings, plants, everything is dependent upon the soil, healthy soil,” he said. “The soil needs to go back to being the carbon sink that it always was, and that it’s made to be.”

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