When some forages are frosted, the potential for bloat, toxicity, and nitrates may increase for grazing cattle.
Troy Walz, University of Nebraska-Lincoln

Bloat
When grazing alfalfa in the fall, bloat remains a potential problem, especially during the first three to five days after alfalfa has been exposed to freezing temperatures. In general, the risk of bloat will be minimal only after a significant portion (about 50-70 percent) of the alfalfa top growth has been frozen and dried. The fall freeze-down is often a slow…