One doesn't need to be a seasoned farmer to know that growing conditions in Canada are completely different than those found in the low desert of California.

And yet, for many years, studies conducted in Canada were used to generate nitrogen uptake data for the California carrot production system, so growers managed their fields based on their own experiences – and that research conducted thousands of miles to the north.

Carrots had been among the crops grown in California that did not have site-specific data to suggest the best source, rate, timing and placement of nitrogen, in the highly variable cropping seasons and locations throughout the state. That's why...