When we graze cover-crops we always need to be considering both meeting the livestock needs as well as soil building objectives. The more cover-crop yield you can produce, the more biomass you can afford to leave behind.
Here is an example of grazing BMR sorghum yielding over 180 AUD/acre while leaving well over one ton of biomass on the ground. This was done with two grazing events. One in the green season and one in the dormant season.
It can be easy to graze too severely especially in the green season. This part of the field does not have enough residue left on the ground. If you want to build soil, you need to be prepared to ‘waste’ a little more grass.
The harvest here was about 120 AUD/acre. Where the manager allowed only 90 AUD/acre, the soil was better protected with trampled residue. This was in early August.
Here are dry cows grazing regrowth on the same field in November. With brown forage, we have a better opportunity to leave more residue on the ground.
The harvest here on the regrowth is just over 90 AUD/acre.
And What About the Economics?
In Nebraska where these photos were taken, pasture grazing rates can be over $50/AUM. Grazing cover-crops can be a real bargain.