Hello,
Great question. Although I think it may be easier to list the vegetation that deer don't eat than the plants that they do....the list would be much, much shorter!
Like Old Buck mentioned: poison ivy is a great whitetail food. They eat the leaves in summer and the berries in the winter (along with birds). They do the same thing with staghorn sumac and they also like to rub the bark on these trees. There are so many other deer foods in the summer season that the list would likely be hundreds of species long. It may be impossible to say which they "prefer" as well, since deer simply take advantage of these foods as they become available. I'd venture to guess that the leaves and buds of 95% of trees and shrubs are browsed and eaten, depending upon seasonal and additional food availability.
About the soybeans you mention: I've found that deer really, really, like them from the time they first start appearing from the soil until the leaves start to turn brown in October. I would say the growth stages of June - August is prime deer food. After the leaves turn brown, deer often shift to other food sources for a short time span before returning to the beans to favor the seeds instead of the leaves.
In the winter time, as other have said, honey locust seeds are prime deer food. These trees often grow in old pasture country where the trees have sprouted via a cow manure pathway (seeds are also spread greatly by deer and birds).
One farm I hunt is virtually 100% honey locust trees (80 acres of honey locust, or so). This farm is jam packed with deer in the winter and the pods get pounded hard! Deer seem to snip open the pods to eat the seeds inside. They are an excellent food source in the late season! Also, the hedge apples of osage orange trees are prime deer and turkey grub in winter. Deer go out of their way to find hedge balls when snow is on the ground, I've found.
Great topic!...
Raven
