Cattle grazing on pasture is a scene most of us can envision. Usually the animals are set against the backdrop of a vibrant green grass. However, grazing doesn’t have to be limited to the growing season. Even now during the heart of winter, dormant season grazing is an option worth considering.
When dormant grazing, we need to take a few things into consideration. First off, does the nutrient value of dormant forages meet the animal’s requirements? While pasture can have fairly high nutritional value, stockpiled grass doesn’t typically top that list. Forage quality is closely correlated with plant maturity, so unless grazing was planned ahead of time to set back plants in the fall, mature grasses will not be of the highest nutritional value.
Additionally, forage has been weathered by rain, snow, wind and changing temperatures, slowly degrading over time. This isn’t to say that dormant grass doesn’t have value, but to maintain animal condition and health, we often need to provide additional protein and sometimes energy to the diet. This is especially true for lactating animals, both fall calving cows still with their calf, or spring calvers once a calf drops.
The second thing we need to keep in mind is protecting the health of the pasture itself. Dormant season grazing has the benefit of utilizing plants when they aren’t actively growing, or dormant. Under normal circumstances, we want to leave behind enough plant to help it recover from the stress of defoliation. While active, the plant is trying to balance this recovery process with building energy stores in the crown and roots to make it through winter. A good rule of thumb to start with in active growth is leaving half of the growing plant behind.
Because the plant has shut down production and isn’t trying to actively recover, we can graze a bit harder without damage. It’s going to start spring with new growth no matter what. This of course comes with a caveat. Overgrazing can still occur during the winter months. Some aboveground growth is beneficial in stopping erosion, protecting the crown for temperature fluctuations, and increasing precipitation and cover by catching snow. Leaving 30-35% of the plant behind during the dormant season is a good goal to shoot for. Keep this in mind, even with pastures that aren’t specifically being used for grazing. Cattle still forage in a calving or winter feeding pasture and it’s very easy to overgraze these areas year after year.
The last thing to think of with dormant season grazing is weather. With good conditions, winter grazing is pretty straight forward. However, when the ground gets muddy or a foot of snow covers the land, things get more difficult. Just how much snow or ice can be a problem for animals grazing is debatable. This back and forth can mostly be attributed to the differences in the forage itself and precipitation we receive. A foot of stockpiled grass or a hay swath with lots of air under ice or snow is going to be easier to break into and get meaningful forage from than a shortly grazed pasture or corn residue lying on the ground.
When it comes to precipitation, what we actually receive can impact availability as well. A heavy, wet snow will be harder to dig through than dry, fluff. For ice, thickness and length of time it is maintained are the two factors to keep in mind. An inch of ice that melts in a day or two after warm temperatures can have less of an impact than ½ inch that sticks around for 3 or 4 days. With each impediment, an animal has to work harder and harder for a bite.
Dormant grazing can be a great opportunity to utilize pastures without the stress of growing season grazing, or to stretch harvested forage resources during the winter months. Having a plan going in, keeping an eye on animal condition and being ready to supplement, and being flexible with weather conditions are key to success. With the right steps, winter doesn’t have to stop your herd from grazing.
-Ben Beckman is a beef systems Extension Educator serving the counties of Antelope, Cedar, Knox, Madison and Pierce. He is based out of the Cedar County Extension office in Hartington. You can reach him by phone: (402) 254-6821 or email: firstname.lastname@example.org .