A New Method for Preventing Snow Mold In Winter Wheat
Each year in early spring, dryland wheat farmers battle for their crop’s survival. As temperatures climb to 0 degrees C, the dark, wet microclimate underneath the snow begins to propagate snow mold.
Wheat spikes in a wheat field.
Soil scientist, Dr. Colin Campbell says, “Soil under a blanket of snow can warm as spring temperatures rise, despite their icy covering. Temperatures above freezing and the water from snowmelt are a perfect environment for mold to grow.“
When faced with these weather conditions, wheat growers know they have only a couple of weeks to remove the snow, or large sections of their crop will die off. Melting the snow artificially can be an expensive process, but one southern Idaho wheat grower has found a unique solution that could save both money and the environment.
Temperatures above freezing and the water from snowmelt are a perfect environment for mold to grow.
The Old Method
Traditionally, wheat growers have spread fly ash (ash from coal) on the spring snow to try and speed the melting process. The black fly ash creates a warmer microclimate by absorbing more solar radiation rather than reflecting it. To demonstrate its effectiveness, the USDA performed studies using fly ash to speed snow melt, with positive results. However, growers say the challenge is using the method in a way that is economical on dryland wheat where the profit margin is narrow. Bryce Campbell, a dryland wheat farmer near Burley, ID, says, “Some people use fly ash to get in the field faster or to get the water flowing into the soil, but our primary goal is to prevent snow mold from killing the winter wheat. If that happens, we have to replant the crop to a spring crop which yields a lot less. Our goal is to try and keep our crop alive.”
During heavy rain events, topsoil washed down to the edges of the field, collecting in dikes Campbell constructed.
An Inexpensive New Method
Campbell has used fly ash in the past, but last year, he had a better idea. He noticed that during heavy rain events, some of his topsoil washed down to the edges of the field, collecting in dikes he constructed and eventually becoming dried and powdery. He wondered if he could use that soil as an economical replacement for fly ash. In the fall, he collected some in a truck and left it to dry completely in the back of his shed; then this season, he spread it over the spring snow. Seeing the results, he decided it was worth the effort, both economically and environmentally. Campbell estimated the fly ash melt to be approximately 30% faster than the powdered soil because of its darker color, but the soil was free, which made a difference in his bottom line.
If snow mold kills the wheat crop, growers have to replant the crop to a spring crop which yields less.
He adds, “Some of the wheat farmers down the road are using a finely ground coal dust product to melt their snow. It’s a great product, and it works really well for melting snow, but their cost is about $20/acre. When you spread that on a thousand acres, that’s $20,000. I can put my soil on a thousand acres, and my only cost is two hours of gathering up the soil plus a day and a half in the tractor for application.”
Next week: Find out which techniques Campbell uses to save time and money redistributing his displaced soil.
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