Here’s hoping everyone had a wonderful Christmas and is looking forward to a fruitful New Year. Instead of continuing to look back at the agricultural events of this past year, let’s examine the benefits of snow for agriculture. While it makes travel difficult and causes headaches for many, including farmers and ranchers, snow is a necessary evil with many benefits for agricultural production.
Terming a layer of snow on the ground a “blanket” is an apt description. Just as a blanket on a bed, it serves to conserve heat in the ground. For wheat farmers this helps protect the wheat plant’s growing point which is an inch or so below the soil surface. First the snow helps to prevent heat loss from the soil to the atmosphere by serving as an insulating barrier between the soil and air. You have seen this insulating effect when it is extremely cold when you shovel snow. The snow next to the ground is slushy while the snow above is fluffy. Since a great deal of the volume occupied by the snow is typically air, snow is really no different than insulation in an attic.
While the air temperature may be close to zero, the soil just twelve inches or so below the surface this time of year may be in the forties. A check of the soil temperature at a four inch depth at the KSRE weather station in Stafford County for December 25 showed the maximum and minimum soil temperature to be the same, thirty-eight degrees, while the air temperature range was forty-one and seventeen. While wheat’s growing point is closer to the surface, under snow cover it should stay above freezing. Wheat’s growing point during dormancy can withstand below freezing temperature, especially with adequate soil moisture but snow cover certainly helps protect it from extremes.
Another added benefit not just for wheat but for pasture and native grasses is as the snow melts it slowly infiltrates into the soil providing soil moisture to help grasses break dormancy and grow in the spring. It does the same for wheat and the added soil moisture helps bare soil stay warmer and helps prevent wheat winterkill from desiccation.
A less obvious benefit is that snow covering vegetation of all types protects it from desiccation from the wind and wind damage in general. The snow by covering the soil helps prevent erosion, especially from wind.
This isn’t to deny the “fun” farmers and ranchers have tending livestock or having to dig out driveways and roads. However, if you ask the vast majority of agricultural producers, the benefits of snow far outweigh the costs.