Feeding whitetail deer hay or corn can kill them, because deer cannot always digest certain foods. Deer digestion involves protozoa and bacteria that typically help break down foods found in their natural habitats. Different micro-organisms help digest different types of vegetation. If a deer has been feeding on aspen or willows, it has built up the micro-organisms that digest only this kind of vegetation. If this same deer suddenly fills its stomach with corn or hay, it may not have enough of the corn- and hay-digesting micro-organisms in its stomach to digest the food. A whitetail deer can literally starve to death with a full stomach.
In addition, deer can become fixated on a food source and that may not be a good thing. Deer will stay near a sure food source, even an inadequate one, rather than seek more sufficient food in other areas. Once food is discovered, deer concentrate around a feeder rather than scattering through the available winter range. Often, they remain in an artificial feeding area getting only half the food they need rather than fighting the snow to use natural browse. They quickly deplete any close-by forage and can stay in a feeder area until they starve to death. This is why spring searches often reveal concentrations of dead deer within the immediate vicinity of feed areas.
So if you still decide to feed whitetail deer in your area, you must feed every day or the deer wil suffer. If you become ill or go on vacation and can no longer feed, the deer that depend on you for food will suffer. Any interruption, whether due to depleted funds, a vacation, a snow storm or a midwinter move to a warmer climate, will eliminate part or all of a deer’s diet. Once a feeding program starts, it must continue until spring when delicate new growth lures deer to resume foraging away from your feeder. Supplemental feeding can help suburban and rural deer and even make for better whitetail hunting in areas where it’s legal.