When you graze cover crops, you have to look at things differently, says provincial beef and forage specialist Karin Lindquist.
“Management means leaving behind enough of a residue on a light graze versus a heavy graze,” she said during a recent West County Ag Tour. “It’s not just the above material that tells you a lot, but it also tells you what’s below ground.”
A high-residue cover means there are a lot of roots under the soil, which is great for water infiltration, microbes, and macrobes (such as earthworms and beetles).
However, cattle producers need to take a good look at pastures that are being grazed, she said.
“It’s your responsibility to look at what’s beneath your feet, what the cows have been biting off, and how much is left behind before you decide when they should be moving on to the next thing,” she said.
With a cover crop, the stocking rate will probably be just a little bit more than for your standard pasture.
“So when you’re doing a stocking rate, you’re going off the animal units so the animal unit is a 1,000-pound cow with or without a calf,” said Lindquist.
As well, most cows are actually heavier than the standard used in stocking rates, so you have to adjust for that. (In the case of a 1,400-pound animal, you’d use 1.4 when calculating the stocking rate.)
“You could be risking yourself to take off too much of the cover crop than you intended,” she said.
Because there is a wide variety of crops in cover crop mixes, nitrates can be an issue, especially after frost. Some crops offer the potential for bloat or fog fever.
“Be careful when you’re introducing and introduce slowly. Make sure they’re on hay or some other dry feed or a grass pasture before they get on a cover crop. Just monitor the crop itself.”
Cows are picky about what they eat, so producers should consider a managed intensive grazing system.
“That way you have better control of the animal movements,” she said. “When you have great control of when they are going and moving, and when they are moving to the next stop and when the next area may get a rest. You can graze it down to an area where there is regrowth potential. This will allow for better nutrient redistribution.”
Grazing cover crops improves water filtration rates, and enables animals to redistribute their nutrients all over the land, she added.