Rain Damage On Cut Hay

You’ve got your hay fields cut, drying, and then Mother Nature decides to rain on your baling plans. It may or may not be a problem. Hay quality losses from rain depends on the timing, the amount, and the frequency of rain.

Bruce Anderson is an Extension forage specialist at the University of Nebraska. He says freshly-cut hay shouldn’t be too affected by a quick shower if the sun comes out afterward and skies clear. You’ll see the most damage if the hay is dry, ready to be baled, and it starts pouring.

"When it’s nice and dry and ready to go into the bale package and then we get a hard, soaking rain, that can do a great deal of damage to the alfalfa. And if we get repeated rain events, that just makes it even worse for us out there," he says. "So, all those different factors really influence what the conditions are going to be like, and then after a rain occurs, what are the drying conditions like after that."

Rain losses basically happen in two ways. One is physical damage, where the force of the rain drops can knock leaves off the stems. The other is leaching of soluble nutrients from the plant, reducing its energy value.

Anderson says the only way to know if soggy hay can be used is to test it.

"If the alfalfa still is fit and able to be baled, taking a forage test and having it analyzed to tell us what the protein, and fiber, and energy contents might be in there will guide us as to how that alfalfa might be best used in any particular livestock operation," he says.