Features Production Research
Cold weather urea losses proven wrong

March 5, 2010, St. Louis, MO — For years, growers and other experts have believed
that nitrogen losses to the air (volatility) from surface-applied urea could
not occur in the cold, but innovative new research has recorded significant
losses in those very conditions.

March 5, 2010, St. Louis, MO — For years, growers and other experts have believed
that nitrogen losses to the air (volatility) from surface-applied urea could
not occur in the cold, but innovative new research has recorded significant
losses in those very conditions.

Rick
Engel, associate professor in the Department of Land Resources and
Environmental Sciences at Montana State University, carried out the research
and said while it is still ongoing results from the first five campaigns have
been unexpected.

“What
we have been seeing are some very large losses,” said Engel.  “We’ve actually seen some of our
largest losses when our urea applications are during the late fall or early
spring period, even when the soil temperatures are near freezing.”

Engel
conducted his study over five campaigns in the hill country of northern
Montana. He uses a unique micrometeorological system in the field, which
collects ammonia gas over time without disrupting the soil environment.

In
three of the first five of these cold-weather studies, more than 30 per cent of
the applied nitrogen was lost. These losses can add up quickly, especially when
conditions are damp as well as cold.

“In
the five campaigns we’ve conducted to date, our losses have ranged anywhere
from three or four per cent up to 40 per cent,” Engel said. “The conditions
that really seem to promote these ammonia losses from urea are prolonged damp
conditions.”