I have observed and received reports of only very slight frost burn on the tips of leaves of alfalfa and winter annual forage crops after the two cold nights last week in Ohio. On Monday, the alfalfa at the Western Agricultural Research Station looked excellent, with just scattered stems showing slight frost burn on the upper leaves. The 2019 late summer seedings also looked excellent. Italian ryegrass and winter wheat on the station showed just a little purpling on the upper leaf tips.
The situation could be a little more severe in certain pockets of the state, depending on the duration of the low night temperatures last week. However, reports from around the state indicate only slight damage to forage crops and they should grow right out of it with no significant effect on forage yields.
If more injury is observed in certain pockets, the recovery will be very dependent on the general health of the stand. The best recovery will be in younger stands where soil pH and fertility are in the optimal range, and the last cutting in 2019 was not taken by early September. If you have observed more severe injury, feel free to contact me with any questions you may have.