The rye will stay green into the late fall after other plants are dormant. Green and tender will attract deer when everything else is brown. Rye tolerates poor soil, and will be at its prime after Oct 1. Haystack's oats and peas planted in the fall is another good idea. Maybe do a plot of each and see what works better with your situation. Both are cheap seeds, but you may need to buy the peas & oats seed in the spring.