Having run a number of grain screeners/dressers and driers over the years, any self respecting deer would lay up in anything other than barley. Barley itch is no fun.
Having said that, because of the dry conditions, winter Barley is showing far longer straw in many areas than wheat, so potentially offers far better cover. I suspect we will have a straw/forage shortage in the coming months.
Where I am in the SE, fallow are venturing into places hitherto ignored in search of grass. It will be interesting to see if we have an early rut, and what the condition of the deer will be when they start.