Were you thinking of mowing them to stimulate new growth to attract the deer? If so, I'd not do that because as Boll Weevil said, the lowere temperatures will soon slow growth anwyay so that when the deer do start eating the plots they'll eat them down sooner if you mow.
I made a smilar mistake several years in a row with a patch of imperial clover that I would mow in late August. Invariably there would be dry weather rather than low temperatures right after mowing and the clover could never catch up with the deer again that year. Last year and this year I mowed earlier and the clover is keeping up with the deer a lot better.