SACRAMENTO, Calif. — This field of tomatoes on Bill Cruickshank’s land will hopefully provide a decent profit while also serving as a great help for what will be planted next.


What You Need To Know

  • Farmers use large quantities of nitrogen fertilizer to help grow crops

  • Nitrogen released in the air destroys the ozone layer, the fertilizer run off also has the potential to contaminate drinking water

  • Fertilizer is the biggest cost for many cereal crop farmers

  • New research shows crops can be grown with the same amount of yield using 20% to 50% less nitrogen fertilizer

“What’s left over from the tomato crop gets the wheat off to a good start by having some of the leftover nutrients,” Cruickshank said.

Cruickshank has been farming wheat for 40-plus years in Yolo County and is also the chairman of the California Wheat commission. And as much as the tomatoes help provide nutrients to grow a decent wheat crop, a little extra fertilizer help is needed, Cruickshank said.

“It requires about a 120 pounds of phosphorus,” he said. “That can be made up of residual phosphorus in the soil, plus what you can add, and then somewhere in the neighborhood of 180 to 200 pounds of nitrogen to reach maximum yield.”

The nitrogen fertilizer added Cruickshank said for his fields work out to be about 160 pounds of fertilizer per acre.

In 2022, fertilizer prices reached record numbers not seen since the 2008 financial crisis due to the war in Ukraine.

According to a University of Illinois report, prices this year are down, but still higher than average. The decline, Cruickshank said, is welcome news for farmers.

“I would say the fertilizer input is the greatest component to it [the most expensive part of farming wheat],” he said.

Not only is the cost high for farmers, but the cost to the environment can also be significant, said UC Davis professor of plant sciences Eduardo Blumwald, who noted that most nitrogen is broken down in the soil and released as nitrous oxide.

“Much of the nitrogen that is being broken down comes back to our air as nitrous oxide,” Blumwald said. “Nitrous oxide as a gas is not very bad, would not affect us, but nitrous oxide dissolves the ozone layer. And because we are losing the ozone layer, our planet is warming.”

That is why his new research in creating cereal crops like wheat that can better capture nitrogen from the air and put it in the soil through slight genetic modification.

The new research will also have added health benefits for humans as much of California’s groundwater is considered at high risk of contamination by nitrogen fertilizer runoff.

Nitrate-contaminated water has been linked to causing various cancers. The main source of the runoff is from farming.

Blumwald’s research will go a long way to reduce global warming and save farmers a lot of money.

“If you will reduce 20% of the nitrogen fertilizer, you are using in the [United] States alone to grow cereals, I think you can save $1.5 billion,” Blumwald said.

With numbers like that or an even smaller reduction in fertilizer use, Cruickshank said any progress is good news.

“I would say that if they’re able to achieve a 5% reduction now, then I would say they could probably get greater gains later on,” he said.

Cruickshank noted that as stewards of the land, any time farmers can be more sustainable and maintain a business, it’s something worth pursuing.