"It breaks your heart," he sighed as he surveyed the once vibrant landscape before him -- curled, yellowed leaves covering the shrunken husks that would have been this year's crop of almonds, had the water arrived.

Their exposed roots are already starting to turn powdery with rot, and the temperature of almost 104 degrees Fahrenheit (40 degrees Celsius) on this summer morning speeds their decomposition.

Moving among them are huge machines that will turn Hartwig's "beautiful prime almond trees" into large piles of woodchips.

- 'Brutal Shock' -

"It's a sudden brutal shock," the farmer said.

Hartwig is in charge of water management for the mega-property of Woolf Farms, an estate of over 20,000 acres (8,000 hectares) around the small market town of Huron.

This is the first time that the farm has had to uproot so many trees before they reach the end of their life.

From drip irrigation systems to cutting-edge sensors installed throughout the property, everything has been designed to optimize the use of water.

But almond trees are very thirsty, and this is a valley that is sorely lacking in water.

After several years of very low rainfall and a particularly dry winter, California authorities turned off the tap to agricultural producers. In April, after a series of calculations, the farm had to face the hard facts.

"There is not enough water on the market" to keep the almond trees alive, Hartwig said. "It's surely painful to make those changes."

And for good reason: The California almond market is worth nearly $6 billion a year.

- 'Bad Guys' -

California produces 80 percent of the almonds consumed worldwide, a market that has doubled in 15 years driven by demand for substitutes for animal products, such as almond milk.

Woolf Farms almonds travel as far as India or Australia. But is that era now over?

"There is a perception that farmers are here to waste water," said Hartwig, his hands tucked into his jean pockets. "It makes us sound like we are the bad guys."

To irrigate the crops they have managed to preserve, Woolf Farms pumps water found deep underground.

"I'm very proud that we can feed the world from here," he said.

"If we don't have the tools to be able to do that, where is that food going to come from?" he asked.

Driving through the estate, which stretches as far as the eye can see, Hartwig pointed to a series of fallow fields.

"Almost all of this would've been farm," he said. "Now it's just a patchwork of crops."

He sighed. "We've done as much as we can."