Winter is tough on whitetails, that is an accepted fact.
You can help the quality of your herd by providing winter plots - that are not necessarily designed as kill plots.
Having what I call green plots - that the deer can browse in when most of the other food is gone, can greatly benefit the deer herd when they need it most.
Come December - at least in our area of the south - most of the mast is gone, all of the crops were long harvested and this green browse can really make the difference for the deer.
This is true not only for the does that are just now settling into pregnancy but also for the bucks that are sufferering from the effects of the rut - both male and female need nutrients at a time when they are pretty hard to find.
In the south, winter wheat, oats, clover and all of the brassica family are key winter plots. Most of the time, we put these in during late October to early November and while we can hunt them, they really come into their own as December winds long and you move into the really hard months of January and February... our season is long over then but the deer really need to nutrition that these plots can help provide.
Supplement your summer plots with some winter plantings... your immediate hunting may improve and you are certainly making an investment in the quality of your deer herd in the long run.
Shown below is a plot that was planted in late October that is just now getting a decent start - lack of rain in November really hurt this plot - this is buck forage oats and rape... the deer are in it pretty hard, so I know it is helping them.
We hunted this plot this year, but resolved not to take any of the does out of it... we never saw any mature bucks in it, so no deer were taken in this plot at all...