The two types of crop injury I would be concerned about include stem damage and spikelet (head) injury. In Image 3 below you can see the brown discoloration and water soaking to wheat stems caused by freeze injury. This injury eventually lead to severe lodging among select varieties (Image 4). If you see this type of injury it would be best to take this field as a forage crop ASAP.
|Image 3. Freeze damage to wheat stem.|
|Image 4. Subtle difference is crop growth stage led to severe lodging due to freeze injury.|
|Image 5. Healthy spikelet and florets.|