10/16/2026
Good reminder about the effects of frost on alfalfa and potential danger to our cattle. I’ll be ready to bring them off pasture and back to barn and hay as soon as frost hits.
A friendly reminder that while the colors are changing and frosts are setting, alfalfa becomes risky to graze. When a hard frost hits your alfalfa, it freezes the fluid inside the plant and bursts the cell walls. This dumps a bunch of easily digestible proteins and sugars into the plant tissue. If livestock eat it, those rich nutrients whip up a thick foam in the rumen, trapping gas and causing serious bloat.
How to Handle It
· Give it 2 weeks: Wait about 14 days after a hard killing frost before turning livestock out onto alfalfa. That gives the stand enough time to dry down and lower its moisture content so it's far safer to graze.
· Look for wilting: The bloat danger drops off significantly once the plants start visibly drying up and wilting.
· Pull 'em off fast: If your stock is already out on alfalfa when a heavy frost hits, get them off the pasture immediately to prevent bloat.
Frost-damaged alfalfa isn't poisonous, but grazing it fresh after a freeze is a quick way to lose livestock if you aren't careful. Give the alfalfa time to dry out before introducing or continuing to graze alfalfa-rich pastures!
-Kelsey Wallisch, Glacierland RC&D Regenerative Agriculture Specialist
