By Megan Webb, Ph.D. Contributing Editor
Preparing for winter storms is inevitable and doesn’t tend to be the favorite chore among operations, but preparedness is essential. On our operation, when a storm is on the horizon, we take time to assess inventory, feed extra hay to cows on pasture and lead them to a location that drains well and has natural windbreaks such as trees, shrubs or stacked round bales. We also gather feed and hay resources, and place them closer to the shelter areas to be more easily accessible. Our goal in doing this is to ensure we have enough nearby feed and hay for our cattle in the event of potential equipment challenges and to attempt to keep cattle dry and out of the wind.
Certainly, we can’t control mother nature, but we do try to help our cattle from being excessively wet in the cold climate. Cattle that have a wet haircoat before temperatures drop are most likely to have significant energy loss. When cattle are wet, it causes a “snowball effect” – cattle exposed to freezing rain and wind have an accelerated reduction in their body temperature and utilize energy reserves to maintain body temperature. That is why winters with more precipitation, especially freezing rain, cause cattle to drop body condition quickly. A good rule of thumb to attempt to mitigate energy loss is to increase energy supplementation 13 percent for every 10° below 30° F. To help keep cattle drier and out of the wind, physical mechanisms can be used to create wind breaks though these need to be built stable enough to uphold harsh winds and snow load. Essentially, allocate 1 foot of windbreak length per head to ensure you have enough protection for your herd.
Excessive amounts of ice and snow can cause fear among livestock building owners about snow load capacity of their existing structures. Due to the added weight, heavy snowfall and freezing ice can cause roof damage, broken truss cords or ultimate structure collapse. The design of residential facilities is set by state statutes and, in states with heavier snowfall, is likely 35 to 42 pounds per square foot (lbs./sf). However, many livestock facilities are only built using a 20 lbs./sf or less, which would be expected to handle 6 feet of dry, fluffy snow or 1 foot of wet, heavy snow.
When creating shelters and barns, it is important to know your unique annual snowfall. When assessing your facility for snow load concerns, it can be challenging because snow density can range from 3 lbs. per cubic foot (lbs./cf) for light, fluffy snow to 21 lbs./cf for wet, heavy snow and ice density is around 57 lbs./cf. One way to estimate snow load on a roof is to go to an area on the ground nearby the shed or barn. Then, cut out .5 cf of snow (12 inches x 6 inches x 12 inches deep) and put it in an empty 5-gallon bucket (It is important to use undisturbed snow.) Then weigh the snow and the bucket. Next, empty out the snow and weigh the empty bucket separately. The difference between the two weights is the weight of the snow. If it weighed 6 lbs., then a full cubic foot of snow weighs 12 lbs.
As cattle producers, we do a pretty good job of placing cattle in well-drained areas to avoid excessive moisture and mud, but sometimes we can create our own disasters, too. When plowing snow, we need to keep in mind that large piles of snow will accumulate excessive moisture during snow melt, so placing that pile in a location with minimal physical disturbance during snow melt is a good idea. Also, to maintain traction in areas of high throughput, we can add surpluses of wood ash, sand, cornstalks, poultry grit or manure.
If you are like me, you are already looking forward to spring but, until then, I hope from one pasture to another this information benefits you, your cattle and operation this winter!